3GPP TSG RAN WG1 Meeting #120-bis	 								                R1-2501723
Wuhan, China, April 7th – 11th, 2025	

Agenda Item:	9.11.1	
Source:	Thales
Title:	NR NTN Downlink coverage enhancements
Document for:	Discussion and decision

Conclusion

In this contribution. we made the following observations and proposals:

Default value of SSB periodicity

Observation 1: It is observed that extending SSB periodicity is a necessary enhancement to support beam hopping in NTN.
Observation 2: According to the RAN1#120 agreement, the maximum default SSB periodicity, apart from the existing 20ms value, is 160ms. Therefore, cells supporting initial access could have SSB periods of 5, 10, 20, 40, 80, or 160ms.

TP for TS 38.213

Proposal 1
The TP below is endorsed for TS38.213 clause 4.1.

Reason for change: Support of extended periodicity of the half frames with SS/PBCH blocks assumed by UE during initial access.
Summary of change: update regarding the maximum value for the periodicity of half frames containing SS/PBCH blocks, assumed by the UE during initial cell selection. Previously, a periodicity of 2 frames (20ms) was the only assumption. With this change, an additional value of 160ms (periodicity of 16 frames) can now also be considered, depending on the capabilities of the UE. 
Consequences if not approved: Rel-19 downlink coverage enhancement at system level is not supported


Monitoring period of PDCCH in the Type0-PDCCH CSS

Proposal 2
For NTN with extended SSB periodicity and for CORESET multiplexing pattern 1, Type0-PDCCH CSS set periodicity is equal to the periodicity of SSB.


Impact on UE’s cell search complexity and delay


Proposal 3
RAN1 to check whether a modification could be done on the channel raster to reduce the overall cell search time. 


Type0-PDCCH link level enhancement

Observation 3: In existing specifications, in FR1 with SS/PBCH block and CORESET multiplexing pattern 1, there are 2 type-0 SS Set in consecutive slots and two candidates SIB1 transmission for each SSB index.  a UE monitors PDCCH in the Type0-PDCCH CSS set over these two slots. In fact, only 1 of the 2 candidates is expected to be used. That is, the gNB can select between the two candidates. However, the UE is supposed to monitor both SS Sets for SIB1 PDSCH resource allocation.

Observation 4: To bridge the gap for PDCCH, 2 dB coverage enhancement are needed, and thereby two repetitions would be enough.

Observation 5: Inter slot repetition is adopted as per RAN1#120 agreement, and since the BD limit is defined per slot, this means that the two PDCCH candidates are counted individually towards the BD limits.

Observation 6: For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, Option 1 can be adopted for M=1 and M=½ when digital beamforming is employed. This requires that at least two simultaneous beams be illuminated. If two beams cannot be illuminated simultaneously, then M=2 could be configured.

Proposal 4 
For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, support repeated PDCCH candidates in the two consecutive slots   and  associated with the same SSB index (  as defined in section 13 of TS 38.213)
Repeated PDCCH candidates share the same aggregation level (AL), coded bits and same candidate index
Note: if the network repeats the Type 0 PDCCH across two consecutive slots, a legacy UE might decode the PDCCH and associated PDSCH in one slot and skip PDCCH monitoring in the other slot. 

Proposal 5
PDCCH repetition for Type0 PDCCH CSS is indicated using reserved bits in PBCH payload.  *

Other CSS type PDCCH link level enhancement

Proposal 6
For PDCCH link level enhancements support intra-slot repetition for Type0A-PDCCH, Type1-PDCCH and Type2-PDCCH.

Proposal 7
For PDCCH CSS (except Type0 and Type3), support linking two SS sets by configuration in SIB1 and dedicated signaling:
When PDCCH repetition is monitored in two linked SS sets, the UE does not expect a third monitored SS set to be linked with any of the two linked SS sets.
The two linked SS sets have the same DCI formats to monitor
The two SS sets should have the same periodicity and offset and the same duration
For linking monitoring occasions across the two SS sets that exist in the same slot: 
The two SS sets have the same number of monitoring occasions within a slot and n-th monitoring occasion of one SS set is linked to n-th monitoring occasion of the other SS set.

Proposal 8
The following SS sets can be linked to another SS set for PDCCH repetition: SS set 0 which is not configured within MIB pdcch-ConfigSIB1, searchSpaceOtherSystemInformation, pagingSearchSpace, ra-SearchSpace and SS set configured by recoverySearchSpaceId.
The parameter SearchSpaceLinkingId should be updated accordingly.

Proposal 9
When two PDCCH candidates are linked for PDCCH repetition, RAN1 to discuss, how they should be counted toward the BD (/ CCE) limit.

Proposal 10
To prevent ambiguity at the UE, a reference PDCCH candidate is defined for various processes such as timing and PDSCH reception.

SIB1 PDSCH link level enhancement

Proposal 11
For SIB1 link level enhancement, support PDSCH repetition of SIB1 transmitted within the same slot as the type0-CSS PDCCH repetition.
UE supporting SIB1 PDSCH coverage enhancement assumes that the PDCCH and associated PDSCH to be repeated in both slots where the corresponding PDCCHs are transmitted.
Each PDSCH SIB1 repetition is within the same slot of each PDCCH candidate for scheduling DCI
The two associated PDSCHs have the same RV

Proposal 12
SIB1 PDSCH repetition is indicated using reserved bits in PBCH payload   

Proposal 13
Introduce a new parameter e.g. type0-pdcchCSSandSIB1repetition is to enable/disable type0-pdcchCSS and/or SIB1 PDSCH repetition.
This parameter is signaled using two reserved bits in PBCH payload in FR1 NTN.   

MSG4 PDSCH link level enhancement

Proposal 14
For Msg4 PDSCH support up to 4 repetitions

Proposal 15
Msg4 PDSCH repetition is configured by SIB1, the following details are provided
Msg4 PDSCH aggregation factor: to define the number of repetitions to be applied to the Msg4 PDSCH transmission.
When the Msg4 PDSCH aggregation factor is configured with a value of n=2 or n=4, the Msg4 PDSCH is repeated in n consecutive slots
The same symbol allocation is assumed for all repetitions
The RV is changed for each repetition to help maximizing the IR soft combining at the UE receiver.

RSRP threshold used by the UE to detect the need for Msg4 PDSCH repetition.


Proposal 16
Msg4 PDSCH repetition is triggered upon UE request via MGS3.

Proposal 17
The Msg4 PDSCH repetition is activated using PDCCH- DCI Format 1_0
FFS: indication details.

3GPP TSG RAN WG1 #120bis			R1-2501725
Athens, Greece, February 17th – 21st, 2025

Agenda Item:	9.11.1
Source:	Moderator (Thales)
Title:	FL Summary #1: NR-NTN downlink coverage enhancements
Document for:	Discussion, Decision

Conclusion

TBC

Appendix I


Appendix II

RAN1#120 made the following agreement:  

Agreement
For NR NTN, support extended periodicity of the half frames with SS/PBCH blocks assumed by UE during initial access. 
The additional default value assumed by UE during initial access (apart from the existing 20ms value) is 160 ms.

Agreement
Support only inter-slot repetition for Type0 PDCCH CSS.

Agreement
For Msg4 PDSCH repetition support, RAN1 to consider:
Option 1: UE specific repetition indication via DCI
Option 2: Msg4 repetition is configured by SIB1
Option 3: Msg4 PDSCH repetition is implicitly determined by SIB1 PDSCH repetition 

Agreement
At least for enabling PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, RAN1 to consider the following options
Option 1: Using the spare 1 bit in MIB
Option 2: Using reserved bit(s) in PBCH payload
Option 3: Using codepoint(s) in PBCH payload
Option 4: UE blind decoding without signaling from the network during initial access

Agreement
For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, consider the following:
Option 1: Support repeated PDCCH candidates in the two consecutive slots   and  associated with the same SSB index (  as defined in section 13 of TS 38.213)
Repeated PDCCH candidates share the same aggregation level (AL), coded bits and same candidate index
FFS: Details including how the two PDCCH candidates are counted toward the BD limits
Note: with option 1, if the network repeats the Type 0 PDCCH across two consecutive slots, a legacy UE might decode the PDCCH and associated PDSCH in one slot and skip PDCCH monitoring in the other slot. 
FFS: whether/how option 1 can be applicable for M=1 and M= ½
Option 2: Support repeated PDCCH candidates in the two slots   and  [or  and  ] associated with the same SSB index (  as defined in section 13 of TS 38.213)
Value of X>1, predefined or configured
FFS: Value of X 
Repeated PDCCH candidates share the same aggregation level (AL), coded bits and same candidate index
FFS: Backward compatibility to legacy UE
Option 3: 
The PDCCH candidates in slots n0 associated respectively with different SSB indexes are repetitions of each other and share the same aggregation level, coded bits and same candidate index
For M=1/2 and M=1, the repeated PDCCH candidates in two consecutive slots associated with different SSB indexes;
For M=2, the PDCCH candidates in slots n0+1 associated respectively with different SSB indexes are repetitions of each other and share the same aggregation level, coded bits and same candidate index
Option 4: Option 2 with cross SSB beam repetition support
The PDCCH candidates in slots n0 associated respectively with different SSB indexes are repetitions of each other and share the same aggregation level, coded bits and same candidate index.

Agreement
For SIB1 link level enhancement, RAN1 to consider the following options:
Option 1: PDSCH repetition of SIB1 is transmitted within the same slot as the type0-CSS PDCCH repetition.
UE supporting SIB1 PDSCH coverage enhancement assumes that the PDCCH and associated PDSCH to be repeated in both slots where the corresponding PDCCHs are transmitted.
Each PDSCH SIB1 repetition is within the same slot of each PDCCH candidate for scheduling DCI
The two associated PDSCHs have the same RV
Option 2: Option 1 and an additional PDSCH with SIB1 repetition can occur after the slot of type0-PDCCH CSS repetition.
FFS: How to schedule the SIB1 repetition
Option 3: The repetition of PDSCH with SIB1 is indicated by the scheduling PDCCH
PDSCH is repeated in two slots
Note: Backward compatibility should be maintained

RAN1#119 made the following agreements and observation:

Agreement
For PDSCH with Msg4 Link level enhancement:
Support PDSCH repetition
FFS: signalling design including number of repetitions
FFS: impact on UE capability
Note: the target coverage enhancement to bridge the gap with respect to single Msg4 transmission is 2.8 dB
Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.

Observation
Backward compatibility for legacy UEs (i.e. Rel-17 and Rel-18 UEs) assuming a default SSB periodicity of 20ms is not guaranteed when SS/PBCH blocks periodicity is larger than 20ms within the cell used for initial frequency scan.
Legacy UEs (i.e. Rel-17 and Rel-18 UEs) are not expected to be able to camp on a cell with SS/PBCH blocks periodicity larger than 160 ms.

Agreement
For link level enhancement of PDSCH with SIB1:
Support PDSCH repetitions within 20 ms duration
The number of repetitions is fixed to 2 repetitions 
Further discuss the specification impact for at least the following:
Procedure and signaling (enabling repetitions, associated time resource determination, etc.)
Note 1: without the above PDSCH repetitions, the coverage gap is 2.2 dB to 4.6 dB depending on SIB1 size.
Note 2: Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.
Note 3: the above is not related to multiple SIB1 transmissions across 20 ms periodicities of SSB, which may not be available when the SSB periodicity is 160 ms or larger (if supported) depending on the SSB and CORESET multiplexing pattern.


Agreement
For PDCCH CSS (except Type-3) link level enhancements, support only PDCCH repetition for NTN.
FFS: intra-slot and/or inter-slot


RAN1#118bis made the following agreements:

Agreement
For NR NTN, support extended periodicity of the half frames with SS/PBCH blocks assumed by UE during initial access. 
The maximum of the additional default value (apart from the existing 20ms value) is at least 160 ms.
FFS: whether 320ms can be supported as the maximum of the additional default value instead of or in addition to 160ms

Agreement
Support PDCCH CSS Link level enhancement in Rel-19 for all CSS types except type 3. 
The following techniques are for further study:
PDCCH repetition, including:
Option 1: Intra-slot PDCCH repetition
Option 2: Inter-slot PDCCH repetition
CORESET length (i.e. number of OFDM symbols) extension 
DCI format optimization (e.g. size reduction, etc)
Note: the same technique is intended to apply to all search space types targeted for link level enhancements
For the above techniques, at least the following aspects should be discussed for the relevant candidate techniques:
Configuration
Backward compatibility and UE behaviour of legacy UE
Linked Search Space
Blocking probability
DCI format size budget
Resource overhead
Impact on CORESET0
Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.
FFS: whether to apply the selected solution to PDCCH CSS type3 and PDCCH USS


Agreement
For PDSCH with Msg4 Link level enhancement:
Continue studying PDSCH repetition
Further discuss the specification impact for at least the following:
Procedure and signaling
Repetition factor
Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.


In this contribution, we delve deeper into the aspects concerning enhancements to DL coverage for NTN: Evaluation of downlink coverage performance on a system level and evaluation of downlink coverage performance on a link level.


RAN1#118 made the following observation and agreement:  

Observation
Based on the results of DL coverage evaluation at system level collected from different sources, it is observed that extending the default value of SSB periodicity (different from 20ms) in NTN with LEO600km satellite parameter sets where the beam footprint diameter is 50 km, is beneficial in terms of reduction of common control channel overhead, when targeting a full coverage of 1058 beam footprints: 
With Set 1-1 FR1 and Set 1-3 FR1, the common messages (SSB, SIB1) overhead is around 40% assuming 5 MHz BW when SSB/SIB1 periodicity of 20ms is in use, this overhead ratio could be reduced to less than 14% when 160ms SSB/SIB1 periodicity is used.
With Set 1-2 FR1, the common message (SSB, SIB1) overhead is greater than 100% assuming 5 MHz BW when SSB/SIB1 periodicity of 20ms is in use, this overhead could be reduced to around 25.8% when 640ms SSB/SIB1 periodicity is used.
Note: the overhead of SIB19 was included in some of the results
Note: an observation when SSB/SIB1 periodicity is 320 ms will be discussed and added to the observation

Agreement
As part of the NTN DL coverage enhancements at both system level and link level, RAN1 to consider:
Extending the periodicity of the half frames with SS/PBCH blocks assumed by UE during initial access. 
Default value[s] with extended periodicity assumed by NTN UE for initial access can be:
One [or more] values from the list {40ms, 80 ms, 160 ms, 320ms, 640ms} 

Potential enhancements for transmitting the DL common channels using a wider beam footprint, while DL/UL dedicated channels (incl. PRACH) may be transmitted using a narrower beam footprint
Link-level enhancements for the following channels:
PDCCH 
PDSCH with Msg 4 
PDSCH with SIB1/SIB19.
Note: link-level enhancements for PDSCH with SIB1/SIB19 may be applicable to other SIBs, without additional specification impact.
Note: the above does not imply that all the channels above will be enhanced, but all of them should be considered based on this agreement

3GPP TSG RAN WG1 #120bis			R1-2501726
Athens, Greece, February 17th – 21st, 2025

Agenda Item:	9.11.1
Source:	Moderator (Thales)
Title:	FL Summary #2: NR-NTN downlink coverage enhancements
Document for:	Discussion, Decision

Conclusion

TBC

Appendix I


Appendix II

RAN1#120 made the following agreement:  

Agreement
For NR NTN, support extended periodicity of the half frames with SS/PBCH blocks assumed by UE during initial access. 
The additional default value assumed by UE during initial access (apart from the existing 20ms value) is 160 ms.

Agreement
Support only inter-slot repetition for Type0 PDCCH CSS.

Agreement
For Msg4 PDSCH repetition support, RAN1 to consider:
Option 1: UE specific repetition indication via DCI
Option 2: Msg4 repetition is configured by SIB1
Option 3: Msg4 PDSCH repetition is implicitly determined by SIB1 PDSCH repetition 

Agreement
At least for enabling PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, RAN1 to consider the following options
Option 1: Using the spare 1 bit in MIB
Option 2: Using reserved bit(s) in PBCH payload
Option 3: Using codepoint(s) in PBCH payload
Option 4: UE blind decoding without signaling from the network during initial access

Agreement
For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, consider the following:
Option 1: Support repeated PDCCH candidates in the two consecutive slots   and  associated with the same SSB index (  as defined in section 13 of TS 38.213)
Repeated PDCCH candidates share the same aggregation level (AL), coded bits and same candidate index
FFS: Details including how the two PDCCH candidates are counted toward the BD limits
Note: with option 1, if the network repeats the Type 0 PDCCH across two consecutive slots, a legacy UE might decode the PDCCH and associated PDSCH in one slot and skip PDCCH monitoring in the other slot. 
FFS: whether/how option 1 can be applicable for M=1 and M= ½
Option 2: Support repeated PDCCH candidates in the two slots   and  [or  and  ] associated with the same SSB index (  as defined in section 13 of TS 38.213)
Value of X>1, predefined or configured
FFS: Value of X 
Repeated PDCCH candidates share the same aggregation level (AL), coded bits and same candidate index
FFS: Backward compatibility to legacy UE
Option 3: 
The PDCCH candidates in slots n0 associated respectively with different SSB indexes are repetitions of each other and share the same aggregation level, coded bits and same candidate index
For M=1/2 and M=1, the repeated PDCCH candidates in two consecutive slots associated with different SSB indexes;
For M=2, the PDCCH candidates in slots n0+1 associated respectively with different SSB indexes are repetitions of each other and share the same aggregation level, coded bits and same candidate index
Option 4: Option 2 with cross SSB beam repetition support
The PDCCH candidates in slots n0 associated respectively with different SSB indexes are repetitions of each other and share the same aggregation level, coded bits and same candidate index.

Agreement
For SIB1 link level enhancement, RAN1 to consider the following options:
Option 1: PDSCH repetition of SIB1 is transmitted within the same slot as the type0-CSS PDCCH repetition.
UE supporting SIB1 PDSCH coverage enhancement assumes that the PDCCH and associated PDSCH to be repeated in both slots where the corresponding PDCCHs are transmitted.
Each PDSCH SIB1 repetition is within the same slot of each PDCCH candidate for scheduling DCI
The two associated PDSCHs have the same RV
Option 2: Option 1 and an additional PDSCH with SIB1 repetition can occur after the slot of type0-PDCCH CSS repetition.
FFS: How to schedule the SIB1 repetition
Option 3: The repetition of PDSCH with SIB1 is indicated by the scheduling PDCCH
PDSCH is repeated in two slots
Note: Backward compatibility should be maintained

RAN1#119 made the following agreements and observation:

Agreement
For PDSCH with Msg4 Link level enhancement:
Support PDSCH repetition
FFS: signalling design including number of repetitions
FFS: impact on UE capability
Note: the target coverage enhancement to bridge the gap with respect to single Msg4 transmission is 2.8 dB
Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.

Observation
Backward compatibility for legacy UEs (i.e. Rel-17 and Rel-18 UEs) assuming a default SSB periodicity of 20ms is not guaranteed when SS/PBCH blocks periodicity is larger than 20ms within the cell used for initial frequency scan.
Legacy UEs (i.e. Rel-17 and Rel-18 UEs) are not expected to be able to camp on a cell with SS/PBCH blocks periodicity larger than 160 ms.

Agreement
For link level enhancement of PDSCH with SIB1:
Support PDSCH repetitions within 20 ms duration
The number of repetitions is fixed to 2 repetitions 
Further discuss the specification impact for at least the following:
Procedure and signaling (enabling repetitions, associated time resource determination, etc.)
Note 1: without the above PDSCH repetitions, the coverage gap is 2.2 dB to 4.6 dB depending on SIB1 size.
Note 2: Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.
Note 3: the above is not related to multiple SIB1 transmissions across 20 ms periodicities of SSB, which may not be available when the SSB periodicity is 160 ms or larger (if supported) depending on the SSB and CORESET multiplexing pattern.


Agreement
For PDCCH CSS (except Type-3) link level enhancements, support only PDCCH repetition for NTN.
FFS: intra-slot and/or inter-slot


RAN1#118bis made the following agreements:

Agreement
For NR NTN, support extended periodicity of the half frames with SS/PBCH blocks assumed by UE during initial access. 
The maximum of the additional default value (apart from the existing 20ms value) is at least 160 ms.
FFS: whether 320ms can be supported as the maximum of the additional default value instead of or in addition to 160ms

Agreement
Support PDCCH CSS Link level enhancement in Rel-19 for all CSS types except type 3. 
The following techniques are for further study:
PDCCH repetition, including:
Option 1: Intra-slot PDCCH repetition
Option 2: Inter-slot PDCCH repetition
CORESET length (i.e. number of OFDM symbols) extension 
DCI format optimization (e.g. size reduction, etc)
Note: the same technique is intended to apply to all search space types targeted for link level enhancements
For the above techniques, at least the following aspects should be discussed for the relevant candidate techniques:
Configuration
Backward compatibility and UE behaviour of legacy UE
Linked Search Space
Blocking probability
DCI format size budget
Resource overhead
Impact on CORESET0
Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.
FFS: whether to apply the selected solution to PDCCH CSS type3 and PDCCH USS


Agreement
For PDSCH with Msg4 Link level enhancement:
Continue studying PDSCH repetition
Further discuss the specification impact for at least the following:
Procedure and signaling
Repetition factor
Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.


In this contribution, we delve deeper into the aspects concerning enhancements to DL coverage for NTN: Evaluation of downlink coverage performance on a system level and evaluation of downlink coverage performance on a link level.


RAN1#118 made the following observation and agreement:  

Observation
Based on the results of DL coverage evaluation at system level collected from different sources, it is observed that extending the default value of SSB periodicity (different from 20ms) in NTN with LEO600km satellite parameter sets where the beam footprint diameter is 50 km, is beneficial in terms of reduction of common control channel overhead, when targeting a full coverage of 1058 beam footprints: 
With Set 1-1 FR1 and Set 1-3 FR1, the common messages (SSB, SIB1) overhead is around 40% assuming 5 MHz BW when SSB/SIB1 periodicity of 20ms is in use, this overhead ratio could be reduced to less than 14% when 160ms SSB/SIB1 periodicity is used.
With Set 1-2 FR1, the common message (SSB, SIB1) overhead is greater than 100% assuming 5 MHz BW when SSB/SIB1 periodicity of 20ms is in use, this overhead could be reduced to around 25.8% when 640ms SSB/SIB1 periodicity is used.
Note: the overhead of SIB19 was included in some of the results
Note: an observation when SSB/SIB1 periodicity is 320 ms will be discussed and added to the observation

Agreement
As part of the NTN DL coverage enhancements at both system level and link level, RAN1 to consider:
Extending the periodicity of the half frames with SS/PBCH blocks assumed by UE during initial access. 
Default value[s] with extended periodicity assumed by NTN UE for initial access can be:
One [or more] values from the list {40ms, 80 ms, 160 ms, 320ms, 640ms} 

Potential enhancements for transmitting the DL common channels using a wider beam footprint, while DL/UL dedicated channels (incl. PRACH) may be transmitted using a narrower beam footprint
Link-level enhancements for the following channels:
PDCCH 
PDSCH with Msg 4 
PDSCH with SIB1/SIB19.
Note: link-level enhancements for PDSCH with SIB1/SIB19 may be applicable to other SIBs, without additional specification impact.
Note: the above does not imply that all the channels above will be enhanced, but all of them should be considered based on this agreement

3GPP TSG RAN WG1 #120bis			R1-2501727
Athens, Greece, February 17th – 21st, 2025

Agenda Item:	9.11.1
Source:	Moderator (Thales)
Title:	FL Summary #3: NR-NTN downlink coverage enhancements
Document for:	Discussion, Decision

Conclusion

TBC

Appendix I


Appendix II

RAN1#120 made the following agreement:  

Agreement
For NR NTN, support extended periodicity of the half frames with SS/PBCH blocks assumed by UE during initial access. 
The additional default value assumed by UE during initial access (apart from the existing 20ms value) is 160 ms.

Agreement
Support only inter-slot repetition for Type0 PDCCH CSS.

Agreement
For Msg4 PDSCH repetition support, RAN1 to consider:
Option 1: UE specific repetition indication via DCI
Option 2: Msg4 repetition is configured by SIB1
Option 3: Msg4 PDSCH repetition is implicitly determined by SIB1 PDSCH repetition 

Agreement
At least for enabling PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, RAN1 to consider the following options
Option 1: Using the spare 1 bit in MIB
Option 2: Using reserved bit(s) in PBCH payload
Option 3: Using codepoint(s) in PBCH payload
Option 4: UE blind decoding without signaling from the network during initial access

Agreement
For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, consider the following:
Option 1: Support repeated PDCCH candidates in the two consecutive slots   and  associated with the same SSB index (  as defined in section 13 of TS 38.213)
Repeated PDCCH candidates share the same aggregation level (AL), coded bits and same candidate index
FFS: Details including how the two PDCCH candidates are counted toward the BD limits
Note: with option 1, if the network repeats the Type 0 PDCCH across two consecutive slots, a legacy UE might decode the PDCCH and associated PDSCH in one slot and skip PDCCH monitoring in the other slot. 
FFS: whether/how option 1 can be applicable for M=1 and M= ½
Option 2: Support repeated PDCCH candidates in the two slots   and  [or  and  ] associated with the same SSB index (  as defined in section 13 of TS 38.213)
Value of X>1, predefined or configured
FFS: Value of X 
Repeated PDCCH candidates share the same aggregation level (AL), coded bits and same candidate index
FFS: Backward compatibility to legacy UE
Option 3: 
The PDCCH candidates in slots n0 associated respectively with different SSB indexes are repetitions of each other and share the same aggregation level, coded bits and same candidate index
For M=1/2 and M=1, the repeated PDCCH candidates in two consecutive slots associated with different SSB indexes;
For M=2, the PDCCH candidates in slots n0+1 associated respectively with different SSB indexes are repetitions of each other and share the same aggregation level, coded bits and same candidate index
Option 4: Option 2 with cross SSB beam repetition support
The PDCCH candidates in slots n0 associated respectively with different SSB indexes are repetitions of each other and share the same aggregation level, coded bits and same candidate index.

Agreement
For SIB1 link level enhancement, RAN1 to consider the following options:
Option 1: PDSCH repetition of SIB1 is transmitted within the same slot as the type0-CSS PDCCH repetition.
UE supporting SIB1 PDSCH coverage enhancement assumes that the PDCCH and associated PDSCH to be repeated in both slots where the corresponding PDCCHs are transmitted.
Each PDSCH SIB1 repetition is within the same slot of each PDCCH candidate for scheduling DCI
The two associated PDSCHs have the same RV
Option 2: Option 1 and an additional PDSCH with SIB1 repetition can occur after the slot of type0-PDCCH CSS repetition.
FFS: How to schedule the SIB1 repetition
Option 3: The repetition of PDSCH with SIB1 is indicated by the scheduling PDCCH
PDSCH is repeated in two slots
Note: Backward compatibility should be maintained

RAN1#119 made the following agreements and observation:

Agreement
For PDSCH with Msg4 Link level enhancement:
Support PDSCH repetition
FFS: signalling design including number of repetitions
FFS: impact on UE capability
Note: the target coverage enhancement to bridge the gap with respect to single Msg4 transmission is 2.8 dB
Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.

Observation
Backward compatibility for legacy UEs (i.e. Rel-17 and Rel-18 UEs) assuming a default SSB periodicity of 20ms is not guaranteed when SS/PBCH blocks periodicity is larger than 20ms within the cell used for initial frequency scan.
Legacy UEs (i.e. Rel-17 and Rel-18 UEs) are not expected to be able to camp on a cell with SS/PBCH blocks periodicity larger than 160 ms.

Agreement
For link level enhancement of PDSCH with SIB1:
Support PDSCH repetitions within 20 ms duration
The number of repetitions is fixed to 2 repetitions 
Further discuss the specification impact for at least the following:
Procedure and signaling (enabling repetitions, associated time resource determination, etc.)
Note 1: without the above PDSCH repetitions, the coverage gap is 2.2 dB to 4.6 dB depending on SIB1 size.
Note 2: Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.
Note 3: the above is not related to multiple SIB1 transmissions across 20 ms periodicities of SSB, which may not be available when the SSB periodicity is 160 ms or larger (if supported) depending on the SSB and CORESET multiplexing pattern.


Agreement
For PDCCH CSS (except Type-3) link level enhancements, support only PDCCH repetition for NTN.
FFS: intra-slot and/or inter-slot


RAN1#118bis made the following agreements:

Agreement
For NR NTN, support extended periodicity of the half frames with SS/PBCH blocks assumed by UE during initial access. 
The maximum of the additional default value (apart from the existing 20ms value) is at least 160 ms.
FFS: whether 320ms can be supported as the maximum of the additional default value instead of or in addition to 160ms

Agreement
Support PDCCH CSS Link level enhancement in Rel-19 for all CSS types except type 3. 
The following techniques are for further study:
PDCCH repetition, including:
Option 1: Intra-slot PDCCH repetition
Option 2: Inter-slot PDCCH repetition
CORESET length (i.e. number of OFDM symbols) extension 
DCI format optimization (e.g. size reduction, etc)
Note: the same technique is intended to apply to all search space types targeted for link level enhancements
For the above techniques, at least the following aspects should be discussed for the relevant candidate techniques:
Configuration
Backward compatibility and UE behaviour of legacy UE
Linked Search Space
Blocking probability
DCI format size budget
Resource overhead
Impact on CORESET0
Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.
FFS: whether to apply the selected solution to PDCCH CSS type3 and PDCCH USS


Agreement
For PDSCH with Msg4 Link level enhancement:
Continue studying PDSCH repetition
Further discuss the specification impact for at least the following:
Procedure and signaling
Repetition factor
Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.


In this contribution, we delve deeper into the aspects concerning enhancements to DL coverage for NTN: Evaluation of downlink coverage performance on a system level and evaluation of downlink coverage performance on a link level.


RAN1#118 made the following observation and agreement:  

Observation
Based on the results of DL coverage evaluation at system level collected from different sources, it is observed that extending the default value of SSB periodicity (different from 20ms) in NTN with LEO600km satellite parameter sets where the beam footprint diameter is 50 km, is beneficial in terms of reduction of common control channel overhead, when targeting a full coverage of 1058 beam footprints: 
With Set 1-1 FR1 and Set 1-3 FR1, the common messages (SSB, SIB1) overhead is around 40% assuming 5 MHz BW when SSB/SIB1 periodicity of 20ms is in use, this overhead ratio could be reduced to less than 14% when 160ms SSB/SIB1 periodicity is used.
With Set 1-2 FR1, the common message (SSB, SIB1) overhead is greater than 100% assuming 5 MHz BW when SSB/SIB1 periodicity of 20ms is in use, this overhead could be reduced to around 25.8% when 640ms SSB/SIB1 periodicity is used.
Note: the overhead of SIB19 was included in some of the results
Note: an observation when SSB/SIB1 periodicity is 320 ms will be discussed and added to the observation

Agreement
As part of the NTN DL coverage enhancements at both system level and link level, RAN1 to consider:
Extending the periodicity of the half frames with SS/PBCH blocks assumed by UE during initial access. 
Default value[s] with extended periodicity assumed by NTN UE for initial access can be:
One [or more] values from the list {40ms, 80 ms, 160 ms, 320ms, 640ms} 

Potential enhancements for transmitting the DL common channels using a wider beam footprint, while DL/UL dedicated channels (incl. PRACH) may be transmitted using a narrower beam footprint
Link-level enhancements for the following channels:
PDCCH 
PDSCH with Msg 4 
PDSCH with SIB1/SIB19.
Note: link-level enhancements for PDSCH with SIB1/SIB19 may be applicable to other SIBs, without additional specification impact.
Note: the above does not imply that all the channels above will be enhanced, but all of them should be considered based on this agreement

3GPP TSG RAN WG1 #120bis			R1-2501728
Athens, Greece, February 17th – 21st, 2025

Agenda Item:	9.11.1
Source:	Moderator (Thales)
Title:	FL Summary #4: NR-NTN downlink coverage enhancements
Document for:	Discussion, Decision

Conclusion

RAN1#120-bis made the following agreements and working assumption:  

Agreement
When PDCCH CSS type-0 repetition is performed, for SIB1 link level enhancement, support PDSCH repetition of SIB1 transmitted within the same slot as the type0-CSS PDCCH repetition.
UE supporting SIB1 PDSCH coverage enhancement assumes that the PDCCH and associated PDSCH to be repeated in both slots where the corresponding PDCCHs are transmitted.
Each PDSCH SIB1 repetition is within the same slot of each PDCCH candidate for scheduling DCI
The two associated PDSCHs have the same RV
FFS: Whether it is supported that type-0 PDCCH repetition is not performed while the PDSCH-SIB1 repetition is performed, and if so whether/how to handle the slot determination.

Agreement
For enabling/disabling SIB1 PDSCH repetition, RAN1 to consider the following options:
Option 1: Using reserved bit(s) in PBCH payload.
Option 2: Using scheduling PDCCH.
Option 3: The enabling/disabling of SIB1 PDSCH repetition is implicitly indicating by the enabling/disabling of Type-0 CSS PDCCH repetition.

Agreement
For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1:
Enabling/disabling using reserved bit(s) in PBCH payload
No UE behavior is defined for UE in connected mode specifically for the case where the network changes its signaling between enabling and disabling PDCCH repetition for Type0 PDCCH CSS.

Agreement
For Msg4 PDSCH repetition scheme, the Msg4 PDSCH is repeated in N consecutive slots:
The same resource allocation is assumed for all repetitions
The supported repetition factors are: 2 and 4
The network configures a single value between 2 and 4 at a given time
The RV cycling is used for each repetition
If N=4:


Agreement
For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, support repeated PDCCH candidates in the two consecutive slots  and  associated with the same SSB index (  as defined in section 13 of TS 38.213) at least for M=2.
Repeated PDCCH candidates share the same aggregation level (AL), coded bits and same candidate index
Note: if the network repeats the Type 0 PDCCH across two consecutive slots, a legacy UE might decode the PDCCH and associated PDSCH in one slot and skip PDCCH monitoring in the other slot. 
Note: further discuss the potential solution for M=1 and M=1/2.


Working assumption
For PDCCH CSS other than Type-0 CSS and other than Type-3 CSS for common search spaces other than SearchSpaceZero, intra-slot PDCCH repetition is supported. 

RAN1 to down select between option 1 and option 2:

Option 1: Use same CORESET and two different SS (SS Set1 and SS Set2)
Linking two PDCCH candidates (adopt the same mechanism for SS linking specified in Release 17)
FFS: Blind decoding limit

Option 2: Use same CORESET associated with one SS which is repeated by introducing symbol domain offset X 
FFS: Blind decoding limit
FFS: details configuration and signalling

Nokia expressed the concern on the above working assumption that this will take physical resources away from intra-slot scheduling for legacy PDSCH.


Agreement
For enabling/disabling Msg4 PDSCH repetition, RAN1 to down-select among the following options:
Option 1: UE specific PDSCH with Msg4 repetition activation indicated via PDCCH- DCI Format 1_0
FFS: indication details.
FFS: whether/how network is informed by the UE that certain conditions are met to trigger Msg4 PDSCH repetition (e.g. RSRP detected at UE is less than x dB) 
Option 2: The enabling/disabling of Msg4 PDSCH repetition is implicitly indicated by the enabling/disabling of SIB1 PDSCH repetition.
Option 3: The enabling/disabling is indicated by SIB1 configuration
FFS: whether/how network is informed by the UE that certain conditions are met to trigger Msg4 PDSCH repetition (e.g. RSRP detected at UE is less than x dB)
FFS: Whether UE reports its capability

Appendix I


Appendix II

RAN1#120 made the following agreements:  

Agreement
For NR NTN, support extended periodicity of the half frames with SS/PBCH blocks assumed by UE during initial access. 
The additional default value assumed by UE during initial access (apart from the existing 20ms value) is 160 ms.

Agreement
Support only inter-slot repetition for Type0 PDCCH CSS.

Agreement
For Msg4 PDSCH repetition support, RAN1 to consider:
Option 1: UE specific repetition indication via DCI
Option 2: Msg4 repetition is configured by SIB1
Option 3: Msg4 PDSCH repetition is implicitly determined by SIB1 PDSCH repetition 

Agreement
At least for enabling PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, RAN1 to consider the following options
Option 1: Using the spare 1 bit in MIB
Option 2: Using reserved bit(s) in PBCH payload
Option 3: Using codepoint(s) in PBCH payload
Option 4: UE blind decoding without signaling from the network during initial access

Agreement
For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, consider the following:
Option 1: Support repeated PDCCH candidates in the two consecutive slots   and  associated with the same SSB index (  as defined in section 13 of TS 38.213)
Repeated PDCCH candidates share the same aggregation level (AL), coded bits and same candidate index
FFS: Details including how the two PDCCH candidates are counted toward the BD limits
Note: with option 1, if the network repeats the Type 0 PDCCH across two consecutive slots, a legacy UE might decode the PDCCH and associated PDSCH in one slot and skip PDCCH monitoring in the other slot. 
FFS: whether/how option 1 can be applicable for M=1 and M= ½
Option 2: Support repeated PDCCH candidates in the two slots   and  [or  and  ] associated with the same SSB index (  as defined in section 13 of TS 38.213)
Value of X>1, predefined or configured
FFS: Value of X 
Repeated PDCCH candidates share the same aggregation level (AL), coded bits and same candidate index
FFS: Backward compatibility to legacy UE
Option 3: 
The PDCCH candidates in slots n0 associated respectively with different SSB indexes are repetitions of each other and share the same aggregation level, coded bits and same candidate index
For M=1/2 and M=1, the repeated PDCCH candidates in two consecutive slots associated with different SSB indexes;
For M=2, the PDCCH candidates in slots n0+1 associated respectively with different SSB indexes are repetitions of each other and share the same aggregation level, coded bits and same candidate index
Option 4: Option 2 with cross SSB beam repetition support
The PDCCH candidates in slots n0 associated respectively with different SSB indexes are repetitions of each other and share the same aggregation level, coded bits and same candidate index.

Agreement
For SIB1 link level enhancement, RAN1 to consider the following options:
Option 1: PDSCH repetition of SIB1 is transmitted within the same slot as the type0-CSS PDCCH repetition.
UE supporting SIB1 PDSCH coverage enhancement assumes that the PDCCH and associated PDSCH to be repeated in both slots where the corresponding PDCCHs are transmitted.
Each PDSCH SIB1 repetition is within the same slot of each PDCCH candidate for scheduling DCI
The two associated PDSCHs have the same RV
Option 2: Option 1 and an additional PDSCH with SIB1 repetition can occur after the slot of type0-PDCCH CSS repetition.
FFS: How to schedule the SIB1 repetition
Option 3: The repetition of PDSCH with SIB1 is indicated by the scheduling PDCCH
PDSCH is repeated in two slots
Note: Backward compatibility should be maintained

RAN1#119 made the following agreements and observation:

Agreement
For PDSCH with Msg4 Link level enhancement:
Support PDSCH repetition
FFS: signalling design including number of repetitions
FFS: impact on UE capability
Note: the target coverage enhancement to bridge the gap with respect to single Msg4 transmission is 2.8 dB
Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.

Observation
Backward compatibility for legacy UEs (i.e. Rel-17 and Rel-18 UEs) assuming a default SSB periodicity of 20ms is not guaranteed when SS/PBCH blocks periodicity is larger than 20ms within the cell used for initial frequency scan.
Legacy UEs (i.e. Rel-17 and Rel-18 UEs) are not expected to be able to camp on a cell with SS/PBCH blocks periodicity larger than 160 ms.

Agreement
For link level enhancement of PDSCH with SIB1:
Support PDSCH repetitions within 20 ms duration
The number of repetitions is fixed to 2 repetitions 
Further discuss the specification impact for at least the following:
Procedure and signaling (enabling repetitions, associated time resource determination, etc.)
Note 1: without the above PDSCH repetitions, the coverage gap is 2.2 dB to 4.6 dB depending on SIB1 size.
Note 2: Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.
Note 3: the above is not related to multiple SIB1 transmissions across 20 ms periodicities of SSB, which may not be available when the SSB periodicity is 160 ms or larger (if supported) depending on the SSB and CORESET multiplexing pattern.


Agreement
For PDCCH CSS (except Type-3) link level enhancements, support only PDCCH repetition for NTN.
FFS: intra-slot and/or inter-slot


RAN1#118bis made the following agreements:

Agreement
For NR NTN, support extended periodicity of the half frames with SS/PBCH blocks assumed by UE during initial access. 
The maximum of the additional default value (apart from the existing 20ms value) is at least 160 ms.
FFS: whether 320ms can be supported as the maximum of the additional default value instead of or in addition to 160ms

Agreement
Support PDCCH CSS Link level enhancement in Rel-19 for all CSS types except type 3. 
The following techniques are for further study:
PDCCH repetition, including:
Option 1: Intra-slot PDCCH repetition
Option 2: Inter-slot PDCCH repetition
CORESET length (i.e. number of OFDM symbols) extension 
DCI format optimization (e.g. size reduction, etc)
Note: the same technique is intended to apply to all search space types targeted for link level enhancements
For the above techniques, at least the following aspects should be discussed for the relevant candidate techniques:
Configuration
Backward compatibility and UE behaviour of legacy UE
Linked Search Space
Blocking probability
DCI format size budget
Resource overhead
Impact on CORESET0
Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.
FFS: whether to apply the selected solution to PDCCH CSS type3 and PDCCH USS


Agreement
For PDSCH with Msg4 Link level enhancement:
Continue studying PDSCH repetition
Further discuss the specification impact for at least the following:
Procedure and signaling
Repetition factor
Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.


In this contribution, we delve deeper into the aspects concerning enhancements to DL coverage for NTN: Evaluation of downlink coverage performance on a system level and evaluation of downlink coverage performance on a link level.


RAN1#118 made the following observation and agreement:  

Observation
Based on the results of DL coverage evaluation at system level collected from different sources, it is observed that extending the default value of SSB periodicity (different from 20ms) in NTN with LEO600km satellite parameter sets where the beam footprint diameter is 50 km, is beneficial in terms of reduction of common control channel overhead, when targeting a full coverage of 1058 beam footprints: 
With Set 1-1 FR1 and Set 1-3 FR1, the common messages (SSB, SIB1) overhead is around 40% assuming 5 MHz BW when SSB/SIB1 periodicity of 20ms is in use, this overhead ratio could be reduced to less than 14% when 160ms SSB/SIB1 periodicity is used.
With Set 1-2 FR1, the common message (SSB, SIB1) overhead is greater than 100% assuming 5 MHz BW when SSB/SIB1 periodicity of 20ms is in use, this overhead could be reduced to around 25.8% when 640ms SSB/SIB1 periodicity is used.
Note: the overhead of SIB19 was included in some of the results
Note: an observation when SSB/SIB1 periodicity is 320 ms will be discussed and added to the observation

Agreement
As part of the NTN DL coverage enhancements at both system level and link level, RAN1 to consider:
Extending the periodicity of the half frames with SS/PBCH blocks assumed by UE during initial access. 
Default value[s] with extended periodicity assumed by NTN UE for initial access can be:
One [or more] values from the list {40ms, 80 ms, 160 ms, 320ms, 640ms} 

Potential enhancements for transmitting the DL common channels using a wider beam footprint, while DL/UL dedicated channels (incl. PRACH) may be transmitted using a narrower beam footprint
Link-level enhancements for the following channels:
PDCCH 
PDSCH with Msg 4 
PDSCH with SIB1/SIB19.
Note: link-level enhancements for PDSCH with SIB1/SIB19 may be applicable to other SIBs, without additional specification impact.
Note: the above does not imply that all the channels above will be enhanced, but all of them should be considered based on this agreement

3GPP TSG RAN WG1 #120bis                                                                                           R1-2501822
Wuhan, China, April 7th – 11th, 2025

Source:	vivo
Title:	Discussions on NR-NTN downlink coverage enhancement
Agenda Item:	9.11.1
Document for:	Discussion and Decision

Conclusion
In this contribution, we provide our views on downlink coverage enhancement for NR-NTN. According to the discussions, we have following observations and proposals: 
Observation 1: If the SSB periodicity is extended to 160 ms, there may be two options for including the additional default SSB periodicity,
Option 1: When operating on NTN bands, UEs may assume the SSB periodicity to be 160 ms
Option 2: For each NTN band, RAN4 to specify the default SSB periodicity (20ms or 160ms)
Compared with Option 1, Option 2 can simplify the implementation and also avoid the unnecessary latency and overheads in the case where the network does not need larger SSB periodicity for ensuring the coverage, e.g., due to sufficient bandwidth.
Observation 2: There are some ways to indicate the repetition of Type-0 CSS PDCCH configured by searchSpaceZero in MIB:
Option 1: Using the spare 1 bit in MIB
Option 2: Using reserved bit(s) in PBCH payload
Option 3: Using codepoint(s) in PBCH payload
Option 3-1: Reserved entries
Option 3-2: Under the assumption of max. bandwidth, the entries with more than 25 PRBs and/or non-zero RB offset
Option 3-3: The entries other than those included in Option 3-1 and 3-2
Option 4: UE blind decoding without signaling from the network during initial access
For the above options, 
Both Option 1 and 3-1 can only deliver 1 bit, which can only indicate the enabling or disabling of PDCCH repetition. Option 2, 3-2 and 3-3 can deliver more information than 1 bit, such as the positions of the PDCCH repetition. 
Option 3-1 and Option 3-2 bar all legacy UEs if PDCCH repetition is enabled, while the other options may allow the legacy UEs to detect the PDCCH at the cost of potential compatibility issues. Particularly, Option 3-3 may induce additional overheads at the network side.
Besides the potential compatibility issue, Option 4 could constrain the scheduling flexibility of the network and induce higher complexity at the UE side during the initial cell search.
Observation 3: For the indication by the reserved bit(s) in MIB or PBCH payload, legacy UEs may detect one of the repeated PDCCH candidates but may not be able to find the scheduled PDSCH. A proper design of PDCCH repetition and/or SIB1 PDSCH repetition is needed to ensure the legacy UEs successfully receiving the subsequent PDSCH.
Observation 4: Among the options for the repetition of Type-0 CSS PDCCH configured by searchSpaceZero in MIB:
Option 1 may require more simultaneously active beams if M and O are not chosen properly, and may raise the compatibility issue.
Option 2 does not raise the compatibility issue as long as X > 1 but may cause additional overheads to transmit the repeated PDCCH candidate in slot n+X. X can be chosen to avoid repeated MO overlapping with a candidate SSB, thus without the need for more simultaneously active beams.
Option 3 may require more simultaneously active beams if O is not chosen properly and require the network to transmit the same DCI and also the scheduled PDSCH in different beams, imposing some scheduling constraints on the network. Depending on M, power superposition can be achieved for PDCCH reception, yet at the risk of compatibility issues.
Option 4 is basically a combination of Option 2 and Option 3, which should be deprioritized until the above options are clear. 
Observation 5: Some of the PDCCH repetition schemes may require more than 1 bit for indication, which should match the number of bits deliverable by the indication scheme.
Observation 6: The mTRP PDCCH repetition scheme only supports intra-slot repetition, while only inter-slot repetition should be supported for Type-0 CSS PDCCH. Therefore, the mTRP PDCCH repetition scheme should not be extended to the Type-0 CSS PDCCH configured by searchSpaceSIB1.
Observation 7: There are several methods to indicate the configuration of Msg4 PDSCH repetition, including
Option 1: 1 or more bits in the DCI scheduling Msg4 PDSCH
Option 2: Configured by SIB1
Option 3: Follow the enabling/disabling repetition of the CSS associated with the scheduling DCI, or the that of SIB1 PDSCH
Although Option 3 has no extra signaling overheads, but it heavily relies on the consistency of the channel quality between the Msg4 PDSCH and the SIB1 PDSCH, and meanwhile imposing undesirable restrictions on the scheduling. Option 1 raises compatibility issue.

Proposal 1: For each NTN band, RAN4 to specify the default SSB periodicity (20ms or 160ms).
Proposal 2: To achieve the flexible configuration of PDCCH repetition, support the following option to indicate the repetition of Type-0 CSS PDCCH configured by searchSpaceZero in MIB,
2 bits by Reserved bit(s) in PBCH payload
Proposal 3: The indication scheme and the repetition scheme for the PDCCH repetition should be jointly considered, to ensure the backward compatibility and sufficient bits deliverable. Support the following option,
Repetition: Option 2 with a X configurable
Indication: 2 bits by Option 2, e.g.,
Codepoint 0: disabled 
Codepoint 1: enabled, X=2
Codepoint 2: enabled, X=3
Codepoint 3: enabled, X=4
Proposal 4: If searchSpaceSIB1 is configured to be zero (i.e., search space #0), the Type-0 CSS PDCCH repetition follows the configuration of Type-0 CSS PDCCH configured by searchSpaceZero. Otherwise, i.e., searchSpaceSIB1 is configured to search space other than search space zero (i.e., in a BWP not overlaps with initial BWP), the Type-0 CSS PDCCH repetition is disabled.
Proposal 5: For the CSS other than Type-0 CSS, searchspace zero should not be used if Type-0 PDCCH repetition is enabled.
Proposal 6: For the CSS other than Type-0 CSS, intra-slot PDCCH repetition can be supported by searchspace linking, i.e., the mTRP PDCCH scheme.
Proposal 7: When Type-0 CSS PDCCH repetition is enabled in SS#0, the repetition is not applied to fallback DCI (e.g., DCI with CRC scrambled by C-RNTI). UE should monitor for separate (cannot jointly decoding) fallback PDCCH candidates respectively in the two slots of the searchspaces where the UE monitors for the repeated Type-0 CSS PDCCH candidates.
Proposal 8: RAN1 to considered whether and how to support the UE capability report on the BD counting, such as per slot, for the Type-0 CSS PDCCH repetition.
Proposal 9: At least the following options can be considered to support the BD counting for inter-slot repetition,
Option 1: Only Case 2 or 3 is considered. In this case, it should be defined in the spec that the BD counted in the later slot is 1. By implementation, UE determines either single or combined PDCCH candidate to be detected.
Option 2: Only Case 1 is considered. In this case, it should be defined in the spec that the BD counted in the later slot is 2. 
Option 3: UE chooses Case 1/2/3. In this case, it should be defined in the spec how to report the BD capability and how to the BD in the later slot correspondingly. 
Proposal 10: Support Option 1 for SIB1 PDSCH repetition.
Proposal 11: The enabling/disabling of SIB1 PDSCH repetition should follow that of Type-0 CSS PDCCH repetition.
Proposal 12: More than two repetitions can be considered for Msg4 PDSCH repetition. The repetition number should be indicated.
Proposal 13: The offset (X) between two consecutive Msg4 PDSCH repetitions can be indicated for better flexibility.
Proposal 14: It is desirable to indicate the configuration of Msg4 PDSCH repetition by SIB1, including enabling/disabling Msg4 PDSCH repetition, the offset between two consecutive Msg4 PDSCH repetitions, and repetition number.
Proposal 15: It is desirable to indicate the UE capability of Msg4 PDSCH repetition by higher layer signalings in MsgA PUSCH or Msg3 PUSCH, e.g., LCID.

3GPP TSG-RAN WG1 Meeting #120-bis	R1-2501841
Wuhan, People’s Republic of China, April 7th – 11th, 2025


Agenda Item:	9.11.1
Source:	Ericsson
Title:	On NR-NTN downlink coverage enhancement
Document for:	Discussion

Conclusion
In the previous sections we made the following observations: 
Observation 1	Network operation cannot be viewed solely in terms of the downlink as the UE is expected to initiate uplink communication following the reception of certain downlink physical channels and signals.
Observation 2	Among all sync-raster frequencies within a given transmission bandwidth, only some of them can be considered candidate sync-raster frequencies, and yet only a subset of them fulfills the conditions to be considered a valid sync-raster frequency.
Observation 3	Accounting for the previous observation, a sync-raster design that is sparser with respect to legacy may not be suitable for small channel bandwidths such as 5 MHz CBW. That is, for a 5 MHz CBW, due to the separation between "clusters," a sparser sync-raster design may result in having only few or no valid candidate sync-raster frequencies to place SSB.
Observation 4	Based on the simulation results for PDCCH with an Aggregation Level (AL) = 8, it is observed that PDCCH with 2 repetitions can fulfil the requirement of 2 dB coverage gap enhancement with respect to CNR of -8 dB with Set 1-3 FR1.
Observation 5	Considering only 2 repetitions allows to limit the signaling overhead associated with PDCCH CSS (except Type 3) repetitions.
Observation 6	Inter-slot repetitions for Type0 PDCCH CSS (2 PDCCH repetitions in total) can be achieved with minimum specification impact by considering Option 1, where the UE monitors and expects to receive PDCCH in the two consecutive slots   and  associated with the same SSB index (  as defined in section 13 of TS 38.213).
Observation 7	In typical NTN deployments with one NTN cell illuminated via one beam, there exists only one SSB with one index and hence consecutive slots for inter-slot repetition of PDCCH in Type0 CSS are always available in the single beam per NTN-cell deployments.
Observation 8	By inspecting different combinations of  and  in Table 13-11 of TS 38.213, there is no overlapping of consecutive slots for indices 8 and 9 even with four SSB indices, and two SSB indices are usable without any overlapping of consecutive slots for indices: 0, 2, 4, 6, 10, 11, 12, 13, 14, 15 while it is not possible to use multiple SSB indices without either partial or full overlapping of consecutive slots for indices 1, 3, 5, 7.
Observation 9	In our understanding, the discussion on whether to support inter-slot or intra-slot for PDCCH repetitions for types "other than Type0," encompasses Type 0A-PDCCH CSS, Type 0B-PDCCH CSS, Type 1-PDCCH CSS and Type 2-PDCCH CSS.
Observation 10	For determining the suitability of using an inter-slot scheme for Type 0A-PDCCH CSS, the legacy procedures are to be analysed (i.e., monitoring, overlapping cases, etc). A similar analysis for types "other than Type 0" should be performed for determining whether an inter-slot or an intra-slot will result in minor complexity and limited specification impact.
Observation 11	To match the coverage gap with respect to -8 dB CNR of Set 1-3, it is desirable to have a maximum of 4 repetitions (i.e., aggregation factor of 4) for PDSCH MSG4 while meeting the BLER target.

Based on the discussion in the previous sections we propose the following:
Proposal 1	RAN1 to consider the mandatory physical channels and signals of both downlink (e.g., MIB, SIB1, PDCCH on CORESET#0, etc.) and uplink (random access procedure related transmissions) while using the same beam hopping pattern for both downlink and uplink communications.
Proposal 2	Given that there exists limited amount of time for Rel-19 normative phase, RAN1 to prioritize the remaining issues of link-level enhancements before studying any further system-level enhancements, e.g., optimization of sync raster points and random-access occasions, which are not critical.
Proposal 3	RAN1 to prioritize supporting 2 repetitions for PDCCH CSS (except Type 3) as it is sufficient to match the coverage gap of 2 dB for PDCCH with respect to SNR of -8 dB with Set 1-3 FR1, which only needs the enabling or disabling of repetitions, but not the indication of number of repetitions.
Proposal 4	RAN1 to consider Option 2: Using reserved bit(s) in PBCH payload for enabling PDCCH repetition for Type0 PDCCH CSS configured within MIB pdcch-ConfigSIB1.
Proposal 5	For single SSB beam per NTN-cell and SSB and CORESET multiplexing pattern 1, Option 1 among the PDCCH repetitions schemes for Type0 PDCCH CSS is applicable to M = 2, M = 1 and M = ½ without any overlapping of consecutive slots and with minimum specification impact.
Proposal 6	For multiple SSB beams per NTN-cell SSB and CORESET multiplexing pattern 1, Option 1 among the PDCCH repetitions schemes for Type0 PDCCH CSS is applicable to M = 2 (i.e., indices 8 and 9 in Table 13-11 in TS 38.213) without any overlapping of consecutive slots associated with four SSB indices.
Proposal 7	For multiple SSB beams per NTN-cell SSB and CORESET multiplexing pattern 1, Option 1 among the PDCCH repetitions schemes for Type0 PDCCH CSS is applicable to M = 1 (i.e., indices 0, 2, 4, 6, 10-15 in Table 13-11 in TS 38.213) without any overlapping of consecutive slots associated with two SSB indices, i.e., either SSB indices = 0 and 2 or SSB indices 1 and 3.
Proposal 8	For multiple SSB beams per NTN-cell SSB and CORESET multiplexing pattern 1, Option 1 among the PDCCH repetitions schemes for Type0 PDCCH CSS is applicable to M = 1/2 (i.e., indices 1, 3, 5, 7 in Table 13-11 in TS 38.213) with either partial or full overlapping of consecutive slots associated with two SSB indices, i.e., either SSB indices = 0 and 2 or SSB indices 1 and 3.
Proposal 9	Option 2 among the PDCCH repetitions schemes for Type0 PDCCH CSS incurs an additional delay to decode the PDCCHs and an increased buffer requirements at the UE as well as the issues of backward incompatibility for the legacy UEs with respect to monitoring of two consecutive slots for Type0 PDCCH CSS.
Proposal 10	Option 3 and Option 4 among the PDCCH repetitions schemes for Type0 PDCCH CSS mainly enforces the UE to receive and combine PDCCHs associated with different SSB indices, which may or may not fulfil the coverage as there is no guarantee that the UE receives the signals with good coverage.
Proposal 11	RAN1 to prioritize Option 1 for PDCCH repetition for Type0 PDCCH CSS configured within MIB pdcch-ConfigSIB1 as it works with minimum specification impact at least for single SSB index per NTN-cell.
Proposal 12	For the support of repetitions for Type0-PDCCH, RAN1 to consider the following legacy procedure in clause 13 of TS 38.213 along with the highlighted complementary statement: “For operation without shared spectrum channel access and for the SS/PBCH block and CORESET multiplexing pattern 1, a UE monitors PDCCH in the Type0-PDCCH CSS set over two slots and when PDCCH repetition is indicated the UE can expect to receive Type0-PDCCH CSS over the two slots.”
Proposal 13	RAN1 to discuss the required number of repetitions (e.g., 2 repetitions) for enhancing Type0A-PDCCH scheduling SIBs other than SIB1, and how the network will configure and indicate the use of repetitions to be received within the SI-window for Type0A-PDCCH.
Proposal 14	For determining whether to support inter-slot or intra-slot for PDCCH repetitions for types "other than Type0," RAN1 strives to minimize the complexity and specification impact with respect to existing procedures (e.g., monitoring procedures) applicable to each of the types "other than Type0".
Proposal 15	RAN1 to consider Option 1 but with a flexibility to use RV cycling on available slots, i.e., PDSCH repetition of SIB1 is transmitted within the same slot as the type0-CSS PDCCH repetition for SIB1 link-level enhancement as it can be supported with minimum specification impact as well as effective for beam hopping implementation in practice without fragmentation of resources.
Proposal 16	RAN1 to further discuss whether link-level enhancements for PDSCH with SIB1 may be applicable to other SIBs, e.g., SIB19.
Proposal 17	RAN1 to determine the number of repetitions required for PDSCH with MSG4 to fulfill the required SNR target of -8 dB as 4.
Proposal 18	RAN1 to discuss whether the number of repetitions for MSG4 should be configurable or fixed.
Proposal 19	RAN1 to prioritize Option 3 to indicate the enabling of repetitions for PDSCH with MSG4 that is to determine implicitly based on the SIB1 PDSCH repetition as it allows to reduce the signaling overhead and the specification impact.
Proposal 20	RAN1 to discuss the necessity and benefits of having an explicit UE capability for the repetitions of PDSCH with MSG4 before introducing it.

3GPP TSG RAN WG1 #120bis	R1-2501847
Wuhan, China, April 7th – 11th, 2025
Agenda item:	9.11.1
Source: 	CCU
Title: 	Discussion on downlink coverage enhancements for NR NTN
Document for:	Discussion
1 

Conclusion
Based on the discussion in the previous sections, the following proposals were made:
Observation 1: No reserved bits remain in DCI scheduling Msg4.
Proposal 1: Support transmit repetition indicator of PDSCH repetition for Msg4 via SIB1.
Proposal 2: Support a 2-bit repetition indicator with a maximum repetition value 4.
Proposal 3: Support using one reserved bit in DCI scheduling SIB1 to enable PDSCH repetition for SIB1.
Proposal 4: Support two repeated SIB1 PDSCHs have the same RV.
5 

3GPP TSG RAN WG1 #120bis                                                     R1- 2501880
Wuhan, China, April 07th – 11th, 2025

Agenda Item:	9.11.1
Source:	Spreadtrum, UNISOC
Title:	Discussion on NR-NTN downlink coverage enhancement 
Document for:	Discussion and decision

Conclusion
In this contribution, we provided views on Redcap positioning. In summary, we have following observations and proposals:
Proposal 1: For PDCCH CSS (except Type-3) link level enhancements, PDCCH with 2 repetitions is enough to achieve the target CNR.
Proposal 2: For the signaling of PDCCH repetition for Type0 PDCCH CSS, the reserved 1 bit of , in PBCH payload can be used for enabling PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero.
Proposal 3: For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, the repeated PDCCH candidates in the two consecutive slots   and  associated with the same SSB index should be supported (i.e., Option 1) and the value of M is limited to 2.
Proposal 4: For signaling and configuration, search space linkage based PDCCH repetition in R17 can be as a start point for PDCCH CSS (except Type-3) link level enhancements except searchSpaceZero.
Proposal 5: For PDSCH with Msg4 Link level enhancement, the candidate repetition number of Msg4 PDSCH can be 2 or 4.
Proposal 6: For PDSCH with Msg4 Link level enhancement, the Msg4 PDSCH repetition can be indicated by DCI scheduling Msg4, Option 1.
Proposal 7: For UE capability of support PDSCH repetition, UE can report its request/capability of Msg4 PDSCH repetition via MAC-CE in Msg3 PUSCH.
Proposal 8: PDSCH repetition of SIB1 is transmitted within the same slot as the type0-CSS PDCCH repetition, i.e., Option 1.

3GPP TSG RAN WG1 #120-bis			                                                         R1-2501890
Wuhan, China, Apr 07th – Apr 11th, 2025
	
Agenda item:	9.11.1 - NR-NTN downlink coverage enhancement
Source: 	Fraunhofer IIS, Fraunhofer HHI
Title: 	Discussion on downlink coverage enhancement for NR NTN
Document for:	Discussion 

Conclusion

Observation 1: The allocation of paging occasions and paging frames should be consistent with the beam hopping pattern, as no paging occasions are expected when the beam is off.
Proposal 1: RAN1 to study the impact of beam hopping and SSB periodicity extension on paging procedure.
Proposal 2: RAN1 to study the impact of beam hopping and SSB periodicity extension on random access.
Observation 2: Common downlink control signaling such as SIB1/SIB19 and uplink control signaling such as PRACH could be used to implement beam-hopping without modifications on the current rel-18 cell DTX/DRX.
Proposal 3: Techniques other than cell DTX/DRX should be considered to implement beam hopping.
Observation 3: In case beam hopping is applied, the beam might not be available to keep the periodicity of CORSET0 and the corresponding SIB1 for FR1 and multiplexing pattern1, which is 20ms.

Proposal 4: RAN1 to extend the periodicity of CORSET0 used to schedule SIB1 and the periodicity of the corresponding SIB1 to at least 160ms for FR1 and multiplexing pattern 1 in case beam hopping is to be applied.

Observation 4: MIB has no additional bits to have the configurations for the linked search space in case of inter-slot type0 CSS PDCCH repetition.

Observation 5: There are free time slots in the different PDCCH monitoring occasions configurations, that could be used for type0 PDCCH CSS repetitions over consecutive time slots.

Observation 6: The second type0 PDCCH monitoring occasion associated with an SSB could be used for type0 PDCCH CSS second repetition.

Proposal 5: RAN1 to study whether to use the second type0 PDCCH monitoring occasion associated with an SSB for type0 PDCCH CSS repetition.

Observation 7: Type0 PDCCH CSS repetition associated with SSB index  for Rel19 UEs might overlap with the first type0 PDCCH monitoring occasion associated with SSB index for legacy UEs in case the number of type0 PDCCH monitoring occasions for type0 PDCCH CSS is set to M=1 or M=1/2.

Observation 8: Type0 PDCCH CSS repetition doesn’t overlap with other type0 PDCCH CSSs in case the number of type0 PDCCH monitoring occasions for type0 PDCCH CSS is set to M =2.

Observation 9: UEs are not expected to have overlapping type0 PDCCH CSSs even when considering repetition over the second type0 PDCCH monitoring occasion, as SSB and its associated type0 PDCCH CSS are transmitted on an NTN beam that is different from the beams used to transmit other SSBs and their associated type0 PDCCH CSSs.
Observation 10: The default applicable PDSCH time resource allocation for type-0 PDCCH CSS (multiplexing pattern 1) is default A, where both PDSCH and PDCCH share the same time slot.

Observation 11: Intra-slot PDCCH repetition might have impact on PDSCH resources allocation for type0 PDCCH CSS, as both PDSCH and PDCCH share the same time slot.

Observation 12: Intra-slot PDCCH repetition might have impact on PDSCH resources allocation for type 0A, type1, and type2 PDCCH CSS in case of default PDSCH time resource allocation type A, were both PDSCH and PDCCH share the same time slot, unless a higher layer signaling is applied to configure both PDCCH and PDSCH in different time slots.

Observation 13: Intra-slot PDCCH repetition for type0 PDCCH CSS might degrade the performance of the scheduled SIB1 message, as both type0 PDCCH CSS and the scheduled SIB1 message share the same time slot.

3GPP TSG RAN WG1 #120bis	R1-2501899
Wuhan, China, April 7th – 11th, 2025

Source:	ZTE Corporation, Sanechips
Title:	Discussion on DL coverage enhancement for NR NTN
Agenda Item:	9.11.1
Document for:   Discussion

Conclusions 
In this contribution, the system level and link level analysis are provided with following observation and proposals.
Proposal 1: Different periodicity per SSB can supported with the consideration on uneven traffic load among different beams. 
Proposal 2: Multiple SSB periodicities and respective SSB index sets can be provided in SIB1 to guarantee measurement precision, power efficiency, and reporting reliability.
Proposal 3: An active time configuration for valid ROs can be used with the usage of beam hopping.
Proposal 4: For enabling PDCCH repetition for Type0 PDCCH CSS, RAN1 consider using the spare 1 bit in MIB. The enabling signaling is applicable for all Type0 PDCCH CSS.
Observation 1: The performance of cross-SSB beam combination is variant for different UEs and beam footprints, which cannot mitigate the coverage gap for sure.
Observation 2: Compared with option 1, option 2 will cause additional cost of blind decoding and buffer requirement.
Proposal 5: For PDCCH repetition for Type0 PDCCH CSS, support repeated PDCCH candidates in the two consecutive slots   and  associated with the same SSB index.
Proposal 6: For PDCCH repetition for Type0 PDCCH CSS, the repeated PDCCH candidates in the two slots is counted as 1 PDCCH candidate.
Observation 3: Inter-slot repetition has already been agreed to be supported for Type0-PDCCH CSS.
Observation 4: Different types of PDCCH CSS can be configured on same search space. Supporting variant repetition solutions for different PDCCH CSS types will caused additional blind decoding complexity and buffer requirement.
Proposal 7: Inter-slot PDCCH repetition should be supported as a unified technique for all PDCCH CSS types except Type3.
Proposal 8: For PDCCH repetition for PDCCH CSS except Type0 and Type3, support repeated PDCCH candidates in two consecutive slots starting from the occasion determined by SS.
Proposal 9: For PDCCH repetition for PDCCH CSS except Type0 and Type3, the repeated PDCCH candidates in the two slots is counted as 1 PDCCH candidate.
Proposal 10: For enabling PDCCH repetition for PDCCH CSS except Type0 and Type3, RAN1 consider to configure together with Type0 PDCCH CSS using the spare 1 bit in MIB. 
Proposal 11: The timing of scheduled transmission should be determined according to the timing of first PDCCH repetition when PDCCH repetition is enabled.
Proposal 12: The repetition of PDSCH with SIB1 is indicated by the scheduling PDCCH. The same time-frequency resource in two consecutive slots starting from the slot scheduled by DCI can be used for SIB1 repetition.
Observation 5: PDSCH with Msg4 has similar performance as PDSCH with SIB1. A same repetition factor can be considered for both of them.
Proposal 13: Msg4 PDSCH repetition is implicitly determined by SIB1 PDSCH repetition.
Proposal 14: For repetition of PDSCH with Msg4, UE capability report may not be needed.

3GPP TSG-RAN WG1 Meeting #120bis	  R1-2501972
Wuhan, China, April 7th – 11th, 2025 

Agenda Item:	9.11.1
Source:	CATT 
Title:	Discussion on downlink coverage enhancement for NR NTN
Document for:	Discussion and Decision

Conclusion
In this contribution we analyse the reference satellite configuration. The downlink enhancement requirements are analyzed from the link level and system level. We have the following proposals and observations:
For SSB extention enhancement:
When UE is capable of conducting SSB detection of 160ms periodicity, it should assume that 160 SSB signal is transmitted from network, which should be captured in TS38.213.
SFN aligmemnt should be supported to reduce implementation complexity when one active beam serves multiple cells.  
The time-segmented bitmap indication method for RO mapping can be supported to adapt to beam hopping mechanism while adhering to the original PRACH resource allocation method as much as possible and without disrupting the mapping rules between SSB and RO.
Consider the solution to resolve paging capacity limitation for 160ms SSB periodicity case. 

For beam hopping case, RO mapping should be TDM based per cell to allow one beam to serve more beam footprints if 160ms SSB periodicity is used.  
Based on current RO mapping rule in specification, RO colliding will be much worse when one active beam serves multiple cells and configure same SFN timing for all cells. 
Maintaining different SFN separately for different cells will lead to high complexity in resource scheduling and beam management, which cause beam hopping unrealizable.
When the SSB periodicity is extended to 160ms and the pagingSearchSpace is configured as zero, the current paging capacity may be insufficient.

For link level enhancement:
Use the reserved bits in the MIB to notify the UE whether the PDCCH is to be repeated.  
Using the existing slot (n0) and an additional slot (n0+X, X>=1) configuration is more flexible and can be applied for any value of M.
Inter-slot repetition can be used for other PDCCH CSS types except Type0 and Type3，and an additional search space can be indicated by a new slot offset configured in system information.
When binding PDSCH with SIB1 to the corresponding PDCCH for joint repetition, PDSCH with SIB1 enhancement does not need additional repetition notification.
When the repetition of PDCCH and PDSCH with SIB1 is 2, it can be divided into two groups including PDCCH and PDSCH, in which the first group is known for legacy UE and Rel-19, and the second group is only aware of Rel-19 UE. 
UE can report the Msg4 repetition capability via 1bit in Msg3.
Using MCS field in DCI scheduling Msg4 to indicate Msg4 repettion times is a prefer option which works similar to Msg3 enhancements. 

For scenarios where M=1 or M=1/2, transmitting the PDCCH in consecutive slots would lead to conflict in the monitor opportunities corresponding to different SSB indexes.
The cross beam transmission schemes will impose strict limitations on the system.
If UE does not report its capability, the base station will treat all UEs as having the same capability (support repetition or not).
 Both of using SIB1 for repetition number indication and binding Msg4 with SIB1 will significantly increase the burden on the base station because of all UEs within the beam will adopt a uniform repetition number.

3GPP TSG RAN WG1 #120bis		                         R1-2502031
Wuhan, China, April 7th – 11st, 2025
Agenda Item:	9.11.1
Source:	China Telecom
Title:	Further Discussion on NR NTN downlink coverage enhancement 
Document for:	Discussion and Decision

Conclusions
In this contribution, we discussed the Rel-19 downlink link-level enhancement and the following proposals are made.
Observation 1: Compared with indicating by cell-level SIB parameters, DCI can perform UE-specific repetition indication with great flexibility.

Proposal 1: For PDSCH with Msg4 link-level enhancement, support indicating Msg4 PDSCH repetition factor via DCI.
Proposal 2: For Type0 PDCCH CSS repetition, support Option 1, i.e., using the spare 1 bit in MIB to enable PDCCH repetition.
Proposal 3: For SIB1 link-level enhancement, support Option 1, i.e., PDSCH repetition of SIB1 is transmitted within the same slot as the type0-CSS PDCCH repetition.

3GPP TSG RAN WG1 #120bis		                                                    R1-2502082
Wuhan, China, April 7th – 11st, 2025

Agenda Item:	9.11.1
Source:	NEC
Title:	NR-NTN downlink coverage enhancement
Document for:	Discussion 

Conclusion
From the discussion, we have the following proposal.

Proposal 1:  Support both inter-slot and intra-slot repetition for Type 1-PDCCH CSS and Type 2-PDCCH CSS to enhance link-level performance.

Proposal 2: Enable UE blind decoding without network signaling during initial access for PDCCH repetition in Type 0-PDCCH CSS (configured via searchSpaceZero within MIB pdcch-ConfigSIB1).

Proposal 3: Support repeated PDCCH candidates in consecutive slots n0 and n0+1 (as defined in TS 38.213 Clause 13) associated with the same SSB index for Type 0-PDCCH CSS repetition in searchSpaceZero.

Proposal 4: Transmit SIB1 PDSCH repetition within the same slots as Type 0-CSS PDCCH repetition to enhance SIB1 link-level performance.

Proposal 5: Support UE-specific repetition indication via DCI for Msg4 PDSCH repetition.

 

3GPP TSG RAN WG1 Meeting #120-bis	R1-2502130
Wuhan, China, April 7th – 11th, 2025
Source:	Fujitsu
Title:	Discussion on downlink coverage enhancements
Agenda Item:	9.11.1
Document for:	Discussion

Conclusion
In this contribution, we provide our views as below.
Observation 1: For enabling PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, selecting Option 1 and 3 should be made carefully from the perspective of forward compatibility and specification impact.

Observation 2: For enabling PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, Option 4 may increase UE power consumption and may affect UE implementation.

Observation 3: For PDCCH repetition mechanism with Option 1 for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, the number of BD to decode combined PDCCH is counted within the BD limits in the slot n0+1.


Proposal 1: For enabling PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, Option 2 should be selected to avoid UE complexity and specification impact.

Proposal 2: For PDCCH repetition mechanism for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, Option 1 should be selected from the coverage ratio perspective and the signalling perspective.

Proposal 3: For PDCCH repetition (except type-0 and type-3), support intra-slot PDCCH repetition.

Proposal 4: For Rel-19 PDCCH repetition (except type-0 and type-3) reusing Rel-17 PDCCH repetition mechanism, the additional SS which monitors the repeated PDCCH should be specified in the time domain after offset x OFDM Symbols from a CSS set which monitors the reference PDCCH.
FFS: offset value x is preconfigured or configured by RRC.

Proposal 5: For all types of PDCCH repetition (except type-0 and type-3), PDSCH should be scheduled by the last repeated PDCCH in the time domain.

Proposal 6: For SIB1 PDSCH repetition, Option 2 should be selected with joint repetition of SIB1 PDSCH and type-0 PDCCH to reduce 1-bit indicator for enabling SIB1 PDSCH repetition and UE complexity and UE complexity.

3GPP TSG RAN WG1 #120bis 	                                           R1-2502173
Wuhan, China, April 7th – 11th, 2025

Source: 	CMCC
Title:	Discussion on NR-NTN DL coverage enhancement
Agenda item:	9.11.1
Document for:	Discussion & Decision

Conclusions
In this contribution, we share our views on DL coverage enhancement for both system-level study and link-level study in NTN scenarios. The observations and proposals are summarized as follows.
Observation 1: Different SSB periodicities can be used to solve the backward compatibility issue, wherein one set of legacy 20ms SSB periodicity can be reserved for legacy NTN UE in some beam footprints, and other sets of longer SSB periodicities can be used to serve Rel-19 NTN UE in other beam footprints.
Observation 2: For LEO-600 Set1-1/1-2/1-3, longer revisit period can be considered to improve the coverage ratio.
Observation 3: Within the dwelling window, the SSB and necessary system information (e.g., SIB1, SIB19) can be broadcasted for the target beam footprints, which can be utilized by UEs to access to the satellite/gNB within the dwelling window. For the residual slots of the dwelling window, it can be used for the dynamic scheduling for the same beam footprints as SSB or other beam footprints.
Observation 4: To provide services to all UEs covered by the satellite footprint, TDM beam scheduling/beam hopping can be performed to illuminate different beam footprint for SSB and necessary system information (e.g., SIB1, SIB19) transmission. 
Observation 5: The time span of the dynamic scheduled dwelling window for a given beam footprint can be allocated based on UE distribution and traffic distribution.
Proposal 1: Considering the extended SSB periodicity of 160ms, the periodicity of Type0-PDCCH monitoring and UE measurement needs to be extended correspondingly.
Proposal 2: Support the system level enhancements to improve the coverage ratio in NR-NTN phase 3, with the consideration of introducing the revisit periodicity and dwelling window for other channels/signals to adapt to SSB periodicity extension.
Proposal 3: Potential enhancements to associate valid ROs among the entire set of configured ROs with an SSB index corresponding to a beam footprint should be considered.
Proposal 4: To improve the association of valid ROs among the entire set of configured ROs with an SSB index corresponding to a beam footprint, the following enhancements can be considered:
Option 1 (Validity Window Based): A validity window associated with a specific SSB index is introduced. ROs configured within this validity window are deemed valid.
Option 2 (Mapping Function Based): A mapping function between the SFN of a specific SSB index and the configured RO index(es) is introduced. The calculated ROs are valid for the corresponding SSB index. 
Alternatively, a mapping bitmap can also be considered.
Proposal 5: For Type-0 PDCCH coverage enhancements, inter-slot PDCCH repetition can be enabled via 1-bit indication in the MIB.
Proposal 6: For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, support repeated PDCCH candidates in the two slots  and , and the slot offset () between PDCCH monitoring window can be predefined separately for different M values.
Proposal 7: For Type0A-PDCCH, Type1-PDCCH and Type2-PDCCH coverage enhancements, inter-slot PDCCH repetition can be supported. 
Proposal 8: To avoid backward compatibility issues for inter-slot PDCCH repetition, potential enhancements to prevent legacy UEs from decoding the non-reference PDCCH can be considered, such as:
Option 1: The non-reference PDCCH is not located in the CSS of the legacy UE.
Option 2: Modify the scrambling sequence of the non-reference PDCCH before modulation (as specified in TS 38.211, Clause 7.3.2.3) to ensure that the legacy UE cannot decode it.
Proposal 9: Considering DL coverage enhancements for PDSCH carrying SIB1/SIB19 in NTN scenarios, enable PDSCH repetition by 1 reserved bit in DCI format 1_0 with CRC scrambled by SI-RNTI.
Proposal 10: For PDSCH with Msg4 link-level enhancement, the following solutions can be considered to support PDSCH repetition,
Enable PDSCH repetition for Msg4 via SIB, and the repetition factor can be indicated if multiple repetition factors are supported.
DCI scheduling PDSCH Msg4 can be used to enable PDSCH repetition with a fixed number of PDSCH repetitions. 

3GPP TSG RAN WG1 #120bis                                  			               R1-2502188
Wuhan, China, April 7th – 11th, 2025


Agenda Item:	9.11.1	
Source:	InterDigital, Inc.
Title:	NR-NTN downlink coverage enhancement
Document for:	Discussion

Conclusions
In this contribution, the following observations are made:
Observation 1: NES Cell DTx and cell DRx mechanisms may provide a baseline for NTN scenarios to enable beam hopping among satellite beams. 
Observation 2: The configuration and signaling mechanisms for NES cell DTx/DRx are not applicable in NTN scenarios. 
Observation 3: A single DTx/DRx pattern may not be suitable for NTN due to wide coverage of satellite beams supporting UEs in different RRC states and with different activity levels. 
Observation 4: SIB1 based indication for Msg4 PDSCH repetition may result in un-necessary Msg4 repetitions.

The observations and the discussion have led to the following proposals:
Proposal 1: Support NTN DTx/DRx mechanisms which determine the transmission/reception of common and UE specific channels/signals.
Proposal 2: Support common signaling for configuration/activation of NTN DTx/DRx mechanisms.
Proposal 3: Support network indication to connected mode UEs an additional active duration for DTx/DRx through the following mechanisms:
Simultaneous activation of multiple DTx/DRx patterns.
Additional active time for the active DTx/DRx pattern. 

Proposal 4: RAN1 investigates the impact of increased SSB periodicity on the following:
System information transmission/acquisition
Paging
Random access
Proposal 5: Support intra-slot PDCCH CSS repetitions, other than for Type0 CSS, using linked search spaces.
Proposal 6: For Msg4 PDSCH repetition, support Option 1, i.e., RAN1 supports the UE specific repetition indication via DCI. 

3GPP TSG-RAN WG1 Meeting #120bis	R1-2502219
Wuhan, China, April 7th-11th, 2025

Agenda Item:	9.11.1
Source:	Huawei, HiSilicon
Title:	Discussion on downlink coverage enhancements for NR NTN
Document for:	Discussion and Decision 

Conclusions
In this contribution, downlink coverage enhancements are discussed based on the link level and system level evaluations according to the agreed methodology in RAN1#116.  The following observations and proposals are proposed:
Observation 1: Managing thousands or hundreds of timing configurations simultaneously would significantly increase the gNB complexity.
Observation 2: Inter-slot PDCCH repetition can be intra-SSB-beam repetition or cross-SSB-beam repetition, which should be further analyzed and discussed.
Observation 3: Intra-SSB-beam PDCCH repetition will cause more resource overhead and prolong the dwell time for the common signal transmission of each beam footprint.
Observation 4: Cross-SSB-beam PDCCH repetition improves PDCCH coverage without additional overhead by combining signals from neighboring beam footprints, thus not affecting the common channel overhead or dwelling time.
Observation 5: Cross-SSB-beam PDCCH repetition is compatible to be jointly used with intra-SSB-beam repetition.
Observation 6: Cross-SSB-beam repetition can also be adopted for PDSCH of SIB1 and SIB19.
Observation 7: Consecutive slot repetition cannot work with intra-SSB-beam repetition for PDCCH in Type0 CSS set, when M=1/2.
Observation 8: Cross-SSB-beam PDCCH repetition can support repetition between two neighboring SSBs, by transmitting PDCCH in consecutive slots (n0 and n0+1) when M=1/2.
Observation 9: Slot n0+Slot n1 repetition can work well jointly with cross-beam repetition, but with higher resource and more complexity on UE, when M=1/2. 
Observation 10: Consecutive slots repetition (i.e., repetitions in slot n0 and n0+1) can work well using cross-SSB-beam repetition, when M=1. 
Observation 11: Consecutive slot repetition cannot work with intra-SSB-beam repetition when M=1.
Observation 12: For M=1, Slot n0 PDCCH repetition + slot n1 PDCCH repetition can work well jointly with cross-beam repetition, but with higher resource and more complexity on UE. 
Observation 13: Cross-SSB-beam PDCCH repetition can be used alone for M=2.
Observation 14: Intra-SSB-beam PDCCH repetition in consecutive slot n0 and n0+1 can ben also used alone for M=2.
Observation 15: Cross-beam PDCCH repetition can be jointly used with intra-SSB-beam in consecutive slots n0 and n0+1 for larger coverage gains.
Observation 16: Slot n0+n1 repetition can work well jointly with cross-beam repetition, but with higher resource and much more complexity on UE.
Observation 17: For M=1 and 1/2, only cross-SSB-beam PDCCH repetition can be used.
Observation 18: For M=2, cross-SSB-beam repetition can be jointly used with intra-SSB consecutive slots repetition.
Observation 19: For Type0 PDCCH repetition details, option 3 and option 4 has no additional resource overhead and can work well with option 1 and option 2 to provide further coverage enhancement. 
Observation 20: For the concerned UEs with link level coverage issue to be resolved in this WI, more than 90% UEs can have higher combined SINR than the required SINR for PDCCH (i.e. -6dB) if two cross-SSB-beam PDCCH repetitions are combined.
Observation 21: Multi-SSB-beams per cell is a reasonable deployment for NTN, which should be at least considered and supported by the specification.
Observation 22: UE can choose the number of cross-SSB-beam combinations depending on decoding performance.


Proposal 1: To support extended SSB periodicity in NR NTN:
For initial cell selection, a UE not supporting the feature of extended default SSB periodicity may assume that half frames with SS/PBCH blocks occur with a periodicity of 2 frames.
For initial cell selection, a UE supporting the feature of extended default SSB periodicity assumes that half frames with SS/PBCH blocks occur with a periodicity of 16 frames and assumes that half frames with SS/PBCH blocks occur with a periodicity of 2 frames.
A UE capability which is conditional mandatory without signalling to be introduced in the Rel-19 NR NTN UE features discussion.
Proposal 2: From RAN1 perspective, option 1 and option 2 are suggested to be further selected by RAN4.
Proposal 3: A validity window is introduced to indicate a subset of RACH occasions, where only the RACH occasions within the window are considered to be valid for PRACH transmission:
The length and an offset to configure the window location are introduced.
Proposal 4: Consider cross-SSB-beam repetition for PDCCH repetition and PDSCH repetition.
Proposal 5: Support cross-SSB-beam repetition for Type0 PDCCH repetition.
Proposal 6: Additionally support intra-SSB-beam repetition in consecutive slot n0 and n0+1, i.e. Option1, for M=2 of Type0-CSS PDCCH.
Proposal 7: Do not consider option 1, i.e. Using the spare 1 bit in MIB, for Type0 PDCCH repetition indication.  
Proposal 8: For Type0 PDCCH repetition indication, option 2 and option 3 are preferred. 
Proposal 9: Similar as Type0-CSS, support cross-SSB-beam repetition for type0A-CSS PDCCH.
Proposal 10: Support option 1, PDSCH repetition of SIB1 is transmitted within the same slot as the type0-CSS PDCCH repetition, as SIB1 repetition enhancement.
Proposal 11: Cross-SSB-beam repetition is either supported for SIB1 PDSCH repetition when cross-SSB-beam repetition is enabled for type0-CSS PDCCH.
Proposal 12: Support option 2, i.e. Msg4 repetition is configured by SIB1 for Msg4 repetition. 
Proposal 13: RAN1 to consider UE request for Msg4 PDSCH repetition transmission, i.e., through Msg3 PUSCH. 

3GPP TSG RAN WG1 #120bis		R1-2502265
Wuhan, China, April 7th – 11th, 2025

Source:	OPPO
Title:	Discussion on NR-NTN downlink coverage enhancement 
Agenda Item:	9.11.1
Document for:	Discussion and Decision

Conclusion
In this contribution, we provide our view and analysis on the system-level and link-level enhancements for downlink coverage in NTN scenario. The following observations and proposals are made:
Observation 1: To support Type0 PDCCH repetition, Option 1 only requires the R19 UE to monitor the repeated PDCCH candidates in the slots   and  associated with the same SSB index for DCI detection, and the backward compatibility can be guaranteed.
Observation 2: Option 1 can be applicable for M=1 and M=1/2, and the potential collision issue can be solved by gNB implementation, e.g., 
gNB transmits the Type0 PDCCH in the overlapping slots associated with different SSB indices with simultaneously active beams;
gNB transmits the Type0 PDCCH repetition associated with different SSB indices in the different SSB periods;
The number of SSB beams is not larger than 2.
Observation 3: Option 2 requires more resources than Option 1 to support Type0-PDCCH repetition.
Observation 4: Option 3 requires the UE to measure and record the 1st and 2nd strongest SSB beam indices, which complicates the cell search procedure, and is not feasible in some cases, e.g., 
When M=1/2, the UE cannot monitor the repeated PDCCH candidates in slots  associates with SSB index 0 and SSB index 1;
When 1 SSB beam per cell is deployed, the UE cannot monitor the repeated PDCCH candidates in slots  associates with different SSB indices.
Observation 5: Besides SSB periodicity extension, extending Type0-PDCCH monitoring periodicity of 20ms can further reduce the common channel overhead to improve the DL coverage ratio.
Observation 6: The inconsistent periodicity between SSB and Type0-PDCCH may degrade the Type0-PDCCH detection performance.
Observation 7: For LEO600 set1-2, only one SI window for SIBx is covered in the active time and other SIBs cannot be transmitted.

Proposal 1: RAN1 to focus on Type0-PDCCH repetition via the existing Type0-PDCCH monitoring occasions.
Proposal 2: For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, RAN1 to support repeated PDCCH candidates in the two consecutive slots   and  associated with the same SSB index (i.e., Option 1). 
Proposal 3: For Type0-PDCCH repetition, the UE counts the repeated PDCCH candidates as 2 PDCCH candidates towards the BD limits.
Proposal 4: Using one of the 2 reserved bits in PBCH payload to inform the UE whether Type0-PDCCH repetition is enabled.
Proposal 5: When PDCCH repetition is enabled for Type0/0A/2-PDCCH CSS set, if the searchspaceID is configured with zero value, the PDCCH repetition scheme for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1 should be reused.
FFS: when the searchspaceID is configured with non-zero value for Type0/0A/2-PDCCH CSS set.
Proposal 6: PDCCH repetition for Type0 CSS set of searchspaceID configured with non-zero value is not supported in R19 NR NTN.
Proposal 7: For Type 0A/2 CSS set of searchspaceID configured with non-zero value, PDCCH repetition is supported by the existing PDCCH monitoring occasions associated with the same SSB index.
Proposal 8: With UE capability report, intra-slot repetition can be considered for Type1-PDCCH repetition.
Proposal 9: For Msg4 PDSCH repetition, the number of repetitions is fixed to 2 repetitions. 
Proposal 10: For Msg4 PDSCH repetition, RAN1 to support Msg4 PDSCH repetition configured by SIB1 (Option 2).
FFS: Repetition request.
Proposal 11: Extending Type0-PDCCH monitoring periodicity should be considered in conjunction with SSB periodicity extension in R19 NR NTN.
Proposal 12: RAN1 considers to transmit multiple SI messages in the same SI window or to transmit different SI messages in different SI periodicities.
Proposal 13: Enhancements on cell DTX/DRX should be considered as the targeted system-level enhancements in R19 NR NTN.
Support a new cell DTX/DRX mechanism, during non-active periods of cell DTX/DRX, the UE does not expect to receive/transmit any signal/channel.
The cell DTX/DRX pattern supported in R19 NR NTN apply to UE in idle mode and connected mode.

3GPP TSG RAN WG1 #120bis    		                           R1-2502383
Wuhan, China, April 7th – 11th, 2025
Agenda item:		9.11.1
Source:			Samsung
Title:			Discussion on downlink coverage enhancement for NR-NTN
Document for:		Discussion and decision

Conclusion
This contribution discusses remaining issues for downlink coverage enhancements. Followings are proposals in this contribution. 
Proposal 1: For Type 0A/1/2 PDCCH CSS repetition, intra-slot PDCCH repetition is supported based on the existing configuration for PDCCH repetition for Type 3 CSS/USS as a baseline. 

Proposal 2: Support option 1 for enabling PDSCH repetition of SIB1

Proposal 3: Support option 1 with only M=2 for enabling Type 0 PDCCH CSS repetition 

Proposal 4: Support option 4 if does not increase UE complexity. Otherwise, choose between option 1 and option 2.
For option 1, confirmation from RAN2 is required if supported in RAN1.
Options 1 and 2 should apply exclusively to NTN.

Proposal 5: Support options 1 and 2 for Msg4 PDSCH repetition with the followings. 
Enabling PDSCH repetition using TDRA table. 
Msg3 PUSCH is used for UE capability reporting

Proposal 6: Support that the maximum number of repetitions of PDSCH with Msg4 is set to 4. 

3GPP TSG RAN WG1 #120bis			R1-2502454
Wuhan, China, April 7th – 11th, 2025

Source: 	Xiaomi
Title:	Discussion on NR-NTN downlink coverage enhancement
Agenda item: 	9.11.1
Document for:	Decision

Conclusions
In this contribution, we present views on NR-NTN DL coverage enhancement, we have the following observations and proposals:
Observation 1: Without the Rel-17 m-TRP framework, the inter-slot repetition route for type 0A/ type 1/ type 2 PDCCH incurs additional specification impacts compared with the intra-slot repetition based on SS linkage approach.

Proposal 1: If RACH enhancement is pursued in Rel-19, the beam hopping pattern specific RO selection can be discussed and optimized.
Proposal 2: Enhancements on Cell DRX/DTX can be considered to support beam hopping in NTN.
During its non-active period UE does not except to receive/transmit any signal from/to the corresponding cell within the corresponding footprint;
A group common DCI can be used to dynamically indicate the beam hopping pattern.
Proposal 3: For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, support option 2 with X = N*M. 
Proposal 4: For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, the AL levels for PDCCH should be larger than a fixed thershold.
Proposal 5: For enabling PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, option 1 and option 2 with kssb is supported. It’s not precluded combining both options if the repetition number exceeds 4.	
Proposal 6:  For SIB1 link level enhancement, RAN1 to consider the following options:
Option 1: PDSCH repetition of SIB1 is transmitted within the same slot as the type0-CSS PDCCH repetition.
UE supporting SIB1 PDSCH coverage enhancement assumes that the PDCCH and associated PDSCH to be repeated in both slots where the corresponding PDCCHs are transmitted.
Each PDSCH SIB1 repetition is within the same slot of each PDCCH candidate for scheduling DCI
The two associated PDSCHs have the same RV
Option 2: Option 1 and an additional PDSCH with SIB1 repetition can occur after the slot of type0-PDCCH CSS repetition.
FFS: How to schedule the SIB1 repetition
Proposal 7: Support UE request and capability indication for msg 4 repetition in msg 3. An RSRP threshold can be configured to UE to trigger such request. 

Proposal 8: Support combined option 1 and 2 by configuring a repetition range and indicating the repetition number.
For indication of the repetition number, either field re-interpretation of MCS or TDRA can be applicable or the TDRA table can be revised to include the repetition number directly. 

3GPP TSG RAN WG1 #120bis			R1-2502473
Wuhan, China, April 7th – 11th, 2025

Agenda item:	9.11.1 (NR-NTN downlink coverage enhancement)
Source: 	NICT
Title: 	Discussion on DL coverage enhancements for NR-NTN
Document for:	Discussion and Decision

Conclusion
Observations
Observation 1:
With maximum SSB periodicity of 160ms, SSB cannot be transmitted to more than half of the beam footprints for satellite parameter set 1-2. Beam footprints without SSB transmission may also occur even for the satellite parameter set 1-1 and 1-3 if legacy SSB periodicity (i.e. 20ms) is applied to some of the beam footprints. They are to be left as out of service area of the satellite.
Observation 2:
Wide beam is one of the measures to eliminate out of service area of the satellite. The specification impact can be minimized if direction-finding capability is assumed in the satellite receiver.
Observation 3:
Narrow beam resolution based on UE location feedback does not require additional signal processing in satellite receiver, but specification for the feedback is required, which can be RO configuration. With special RO configuration, UE capability of locating itself may not be required. 
Observation 4:
SSB transmission using narrow beam is a valid option if beam footprints without SSB transmission are not left as out of service area.
Observation 5:
By proper SSB transmission arrangement that can be done without specification impact. SSB detection for the UEs under beam footprints without SSB transmission can be improved though it would rely much on signal processing in satellite receiver. It can be reduced if location-based RO configuration is introduced. 

Proposals
Proposal 1:
RAN1 to consider the specification of RO with which the UE can select the RO by its location. 

3GPP TSG RAN WG1 #120bis	  	                                      R1-2502488
Wuhan, China, April 7th – 11th, 2025

Agenda Item: 	9.11.1
Source: 	Baicells
Title:	Discussion on downlink coverage enhancement for NR NTN
Document for:	Discussion and Decision



1. 

Conclusions


Observation 1:  It is feasible to use the spare 1 bit in MIB for the enhancement of PDCCH. But this spare bit should be used more fully and effectively.

Proposal 1:  Use the spare 1 bit in MIB for PDCCH, SIB1 and Msg4 enhancement as a whole.

Observation 2: For the benefit of PDCCH combination, the payloads (DCIs) should be same. Therefore the two associated PDSCHs for SIB1 should have the same RV. SIB1 should be within the same slot as the scheduling DCI when the k0 is 0. 

Proposal 2:  For SIB1 link level enhancement, support Option 1: PDSCH repetition of SIB1 is transmitted within the same slot as the type0-CSS PDCCH repetition. UE supporting SIB1 PDSCH coverage enhancement assumes that the PDCCH and associated PDSCH to be repeated in both slots where the corresponding PDCCHs are transmitted. Each PDSCH SIB1 repetition is within the same slot of each PDCCH candidate for scheduling DCI. The two associated PDSCHs have the same RV.

Observation 3: The coverage gaps is 2.8 dB for Msg4 (when payload is 1040 bits) for satellite parameter set 1-3. Therefore it is reasonable to specify the Msg4 repetition factor to be 2.

Proposal 3: Specify the Msg4 repetition factor to be 2.
Observation 4: For Msg4 PDSCH repetition, both UE-specific repetition indication via DCI and configuration of Msg4 repetition by SIB1 introduce specification impacts. There are no additional specification impacts if Msg4 repetition is implicitly determined by SIB1 PDSCH repetition.

Proposal 4: For Msg4 PDSCH, the repetition shall be implicitly determined by SIB1 PDSCH repetition.

Proposal 5: For NTN downlink channel enhancement, PDCCH, SIB1 and Msg4 shall share the same signaling indication.




4. 

3GPP TSG RAN WG1 #120bis		                                                       R1- 2502519
Wuhan, China, April 7th – 11st, 2025

Agenda item:	9.11.1 
Source: 	ETRI
Title: 	Discussion on NR-NTN downlink coverage enhancement 
Document for:	Discussion/Decision

Conclusions
Observation 1: By reusing the signaling mechanism for configuring the number of PUCCH repetitions for Msg4 HARQ-ACK, as specified in Rel-18 NR NTN, both Option 1 and Option 2 can be employed simultaneously.
Observation 2:  Signaling for enabling/configuring PDCCH repetition can reduce unnecessary overhead.
Proposal 1: RAN1 to support at least two repetitions of PDSCH with Msg4.
Proposal 2: RAN1 to support Option 1 and Option2 for Msg4 PDSCH repetitions.
Proposal 3: RAN1 to consider a method combining Option 1 and Option 2 for Msg4 PDSCH repetitions: Adopting the similar signaling mechanism used for PUCCH repetitions for Msg4 HARQ-ACK in Rel-18 NR-NTN.
Proposal 4: RAN1 to consider the RSRP measuring and threshold-based reporting for UE request/capability reporting for Msg4 PDSCH repetition transmission.
Proposal 5: RAN1 to consider initiating the Msg4 PDSCH repetitions at gNB based on the measured signal strength of Msg1 or Msg3.
Proposal 6: RAN1 to downselect the signaling options for supporting Msg4 PDSCH repetition.
Proposal 7: RAN1 to consider reused the field in DCI format 1_0 with CRC scrambled by SI-RNTI to indicate SIB1 repetition.
Proposal 8: RAN1 to consider signaling for PDCCH CSS repetition.
Proposal 9: RAN1 to discuss whether enhancements to the timing relationship are required when extending the default SSB periodicity.

3GPP TSG RAN WG1 #120bis	R1-2502532
Wuhan, China, 7 – 11 April 2025 

Agenda item:		9.11.1
Source:	Nokia, Nokia Shanghai Bell
Title:	Discussions on downlink coverage enhancements
WI code:	NR_NTN_Ph3
Release:	Rel-19
Document for:		Discussion and Decision

Conclusion
In this contribution we have presented our observations and proposals for the DL coverage enhancements. These are as follows:
Observation 1: Adjusting the SMTC window and measurement gaps in case of dynamically changing SSB periodicity will increase the signalling overhead. 
Observation 2: A UE typically needs to measure only a very limited number of cells and not all neighbors of the serving cell.
Observation 3: Providing area specific SMTC windows increases the overhead and UE power consumption due to the extra signaling.
Observation 4: RAN1 work normally focused on defining signals and procedures that focus on UE actions rather than network deployment configuration.
Observation 5: Based on Cell DTX/DRX in Rel-18, only one active period can be configured for a cell DTX with assumption of the different pattern for Cell DTX and Cell DRX or different serving cell.
Observation 6: Only one semi-static cell DTX pattern is neither optimal nor preferred due to variable user and traffic distribution, and it will cost significant signalling overhead for changing cell DTX pattern within a satellite.
Observation 7: The FR1 set 1-2 deployment scenario does not constitute a deployment scenario where it is realistic to be able to provide 100% geographical coverage and at the same time provide data coverage.
Observation 8: For Option 1, and when  or , the repetitions in slots associated with different SSB indexes lead to an increase in interference and impact the blind decoding budget. 
Observation 9: In option 2, with proper design of offset parameter , the repetitions in the non-colliding slots associated with the same SSB index provides stable performance/coverage gain due to double time domain resource utilization.
Observation 10: With option 3, the targeted repetition gain may not be achieved as the performance depends on the location of the UE. Especially, for UEs at the cell edge, that are more in need of coverage improvement.
Observation 11: With option 4, on top of the stable time domain repetition gain, for the UEs that have overlapped beam coverage, the additional cross SSB beam repetition gain is expected.
Observation 12: based on the current specification, at most two SS sets of the same type (i.e., either CSS or USS set) with the same DCI format can be linked together. Additionally, not all CSS types can be linked together.     
Observation 13: In the framework of two linked SS sets, for MOs with the same index in a slot (from each SS set), UE monitors PDCCH candidates  with the same value (from each set, i.e., ). Furthermore, UE’s expectation is that both SS sets have the same periodicity, offset, duration, maximum number of PDCCH candidates per aggregation level, and a same number of non-overlapping PDCCH MOs within a slot.  
Observation 14: The UE is not intended to decode a PDSCH scheduled with SI-RNTI when modulation order is greater than 2 (QPSK). Therefore, MCS bits can be exploited to carry signalling for enabling SIB PDSCH repetitions. However, backwards compatibility must be considered for such an approach.
Observation 15: There is some room for reserved bits to carry the signaling information for enabling SIB PDSCH repetitions, but feasibility of such solutions may be challenging, given that UE does not know at this stage if the network supports the feature or not. 
Observation 16: In case of SSB and CORESET0 multiplexing pattern 1, the PDCCH scheduling SIB1 (Type0-PDCCH) and PDSCH conveying SIB1 are in the same slot.
Observation 17: Option 1 of PDSCH repetition for SIB1 preserves backward compatibility, makes efficient utilization of newtork resources, and leads to the minimum specification impact. 
Observation 18: Option 1 of PDSCH repetition for SIB1 may impose a challenge for UE I/Q sample storing. 
Observation 19: Option 2 of PDSCH repetition for SIB1 requires additional SIB1 transmission after the slot of type0-PDCCH CSS repetition, therefore, increasing network resource consumption and impacting the network spectral efficiency.

Proposal 1: RAN1 to study how a UE can do a scan for neighboring cells over a period with the purpose of limiting the measurements afterwards to the relevant cells.
Proposal 2: RAN1 to ask RAN2 to study the possibility of setting the SSB periodicity to a lower value during mobility events in case of Earth Fixed Cells.
Proposal 3: RAN1 should refrain from using the term “Beam hopping”, since it is not defined in RAN1 specifications.
Proposal 4: RAN1 should focus on defining signals and procedures that allows for the situation of a satellite not being able to have all satellite beams simultaneously active.
Proposal 5: RAN1 should further define the assumptions for the beam activity.
Proposal 6: RAN1 to clarify what is meant with DL beam activity.
Proposal 7: RAN1 to clarify if it is expected to also have UL beam activity patterns.
Proposal 8: RAN1 to clarify if there is a coupling between DL and UL beams.
Proposal 9: RAN1 to exclude FR1 set 1-2 from future considerations due to lack of ability to provide data services for 100% geographical coverage.
Proposal 10: RAN1 to investigate the aspects of more than one active period being configured for dynamic scheduling of DL data in RRC connected mode or Msg2/Msg4/MsgB during initial access.
Proposal 11: RAN1 to select Option 1, using the spare 1 bit in MIB, for enabling PDCCH repetition for Type0 CSS of searchSpaceZero.
Proposal 12: RAN1 to select either Option 2, or Option 4 for Type0 PDCCH CSS of searchSpaceZero.
Proposal 13: For Type-1 PDCCH with CRC scrambled with RA-RNTI, the repetition factor is configured or indicated via SIB1.
Proposal 14: To support a unified framework for coverage enhancement of CSS PDCCH (i.e., via inter-slot repetition), RAN1 to consider Type-1 PDCCH repetitions based on either a) the framework of PDCCH monitoring over a group of slots, or b) the framework of linking two search space with the enhancement of application of the framework to inter-slot linking of two PDCCHs.
Proposal 15: RAN1 to discuss and study methods of signaling for enabling repetition of PDSCH conveying SIB1 and the associated time resource determination.
Proposal 16: RAN1 to consider introducing a new DCI format 1-0 with different RNTI to support SIB PDSCH repetitions and PDCCH coverage enhancement.  
Proposal 17: RAN1 to select Option 1 of PDSCH repetition for SIB1. 
Proposal 18: RAN1 to discuss solutions for UE to report scheduling assistant information for assisting the gNB scheduling of Msg4 PDSCH repetition factor. 
FFS: Information that needs to be included in the assistant information
FFS: Means for signaling of assistant information 
Proposal 19: For indication of repetition factor of PDSCH carrying Msg4, RAN1 to select Option 1 (i.e., UE specific repetition indication via DCI), wherein either use “reserved bit” to introduce a new field, or to use “TB scaling bits” in DCI format 1_0 with CRC scrambled with RA-RNTI.
Proposal 20: RAN1 to consider UE capability indication, for reception of PDSCH carrying Msg4 with repetition, via Msg1.     
Proposal 21: RAN1 to further discuss the higher layer parameters to use for DL coverage enhancements for NR over NTN.

3GPP TSG RAN WG1 #120bis                                                                                              R1-2502549
Wuhan, China, April 7th – 11th, 2025

Source:               TCL
Title:                    Discussion on NR-NTN Downlink Coverage Enhancement
Agenda item:      9.11.1
Document for:    Discussion and Decision

Conclusion
In this contribution, the following proposals have been made:
Proposal 1: When extended periodicity of SSB is assumed, the definition of “beam hopping” needs to be clarified, e.g., beam hopping can be applied to both DL and UL beam pairs, when a beam is activated, both DL and UL can be regarded as activated simultaneously. 
 Proposal 2: For the default SSB periodicity extension and beam hopping, a valid time window associated with the SSB for the PDCCH monitoring in the type0-PDCCH CSS can be defined.
Proposal 3: The impacts of “beam hopping” on the random access procedure need to be studied, particularly with respect to the RAR window and RA contention resolution time window. 
Proposal 4: For common PDCCH coverage enhancement, enabling PDCCH with repetition in the time domain can be considered. 
Proposal 5: For enabling type 0 PDCCH with repetition, explicit indication via  MIB can be considered. 
Proposal 6: For enabling other types of CSSs PDCCH with repetition, except for type 0, explicit indication via SIB1 can be considered. 
Proposal 7: Support repeated PDCCH candidates in the two consecutive slots   and  associated with the same SSB index. 
Proposal 8: For common PDCCH coverage enhancement, enlarging aggregation level can be considered.
Proposal 9: For PDSCH conveying SIB1/Msg4 coverage enhancement, repetition in the time domain can be considered.
Proposal 10: For enabling Msg4 PDSCH repetition, the repetition number can be joint coding with TDRA. 
Proposal 11: For enabling SIB1 PDSCH repetition,  the scheduling DCI of SIB1 can be considered. 
Proposal 12: PDSCH repetition of SIB1 can be transmitted within the same slot as the type0-CSS PDCCH repetition.
4. 

3GPP TSG RAN WG1 #120bis	R1-2502559
Wuhan, China, April 7th – 11th, 2025

Source:	Panasonic
Title: 	NR-NTN Downlink Coverage Enhancement
Agenda Item:		9.11.1 
Document for:	Discussion and decision

Conclusion
We propose the following:

Proposal 1: Support intra-slot for PDCCH repetition for PDCCH CSS (except Type-0 and Type-3)
CORESET is repeated to allow combining before blind decoding.
1st CORESET is signaled via existing IE whole 2nd CORESET is signaled via new IE to allow backward compatibility (i.e., allow legacy UE to receive 1st CORESET). 

Proposal 2: For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, consider the following:
Option 1: Support repeated PDCCH candidates in the two consecutive slots   and  associated with the same SSB index (  as defined in section 13 of TS 38.213)
Repeated PDCCH candidates share the same aggregation level (AL), coded bits and same candidate index
FFS: Details including how the two PDCCH candidates are counted toward the BD limits
Note: with option 1, if the network repeats the Type 0 PDCCH across two consecutive slots, a legacy UE might decode the PDCCH and associated PDSCH in one slot and skip PDCCH monitoring in the other slot. 
FFS: whether/how option 1 can be applicable for M=1 and M= ½

Proposal 3: For SIB1 link level enhancement, RAN1 considers the following:
Option 1: PDSCH repetition of SIB1 is transmitted within the same slot as the type0-CSS PDCCH repetition.
UE supporting SIB1 PDSCH coverage enhancement assumes that the PDCCH and associated PDSCH to be repeated in both slots where the corresponding PDCCHs are transmitted.
Each PDSCH SIB1 repetition is within the same slot of each PDCCH candidate for scheduling DCI
The two associated PDSCHs have the same RV

Proposal 4: RAN1 considers a common signaling design for enabling DL coverage features
Alt 1: MIB or PBCH payload (using Option 1, 2 or 3) indicates enabling of DL coverage features.
Alt 2: Type0-PDCCH and SIB1-PDSCH are received by UE blind decoding without signaling from network (Option 4), and SIB1 indicates enabling of DL coverage features.

Proposal 5: For the number of repetitions of PDSCH with Msg4 up to four repetitions are supported.

Proposal 6: RAN1 considers to signal Msg4 PDSCH repetitions
DCI indicates the number of repetitions via DAI field
Configure sets of number of repetitions for Msg3 PUSCH and Msg4 PDSCH for each codepoint of DAI field.

Proposal 7: RAN1 considers to signal Rel-19 UE capability report via one of two options: 
Alt-1: PRACH
Alt-2: Msg3 

3GPP TSG RAN WG1 #120bis			R1-2502629
Wuhan, China, April 7th – 11st, 2025
 
Agenda Item:	9.11.1
Source:	Apple
Title:	On NR-NTN Downlink Coverage Enhancement
Document for:	Discussion/Decision

Conclusion
In this contribution, we provided our views on the downlink coverage enhancements. Our observations and proposals are as follows:

Observation 1: For inter-slot type0-PDCCH CSS repetition, if PDCCH repetitions occur in consecutive slots and there is more than 1 SSB per cell, then either of the following occurs:
multiple simultaneous satellite beams are required for a cell which reduces the system level coverage,
type0-PDCCH transmissions for certain SSB beams are delayed which reduces the system level coverage,
a satellite beam has power split which reduces PDCCH link level coverage. 

Proposal 1: For inter-slot type0-PDCCH CSS repetition, support repeated PDCCH candidates in two slots ( and ) associated with the same SSB index (Option 2), 
where , with  being the maximum number of SSB beams allowed for a frequency band and M being configured in MIB.

Proposal 2: For inter-slot type0-PDCCH CSS repetition, a capable UE performs blind decoding at slot  in a legacy way, and performs blind decoding at slot  by combining LLRs received at slot  and slot .
FFS whether there is aggregation level restriction for type0-PDCCH repetition.

Proposal 3: For inter-slot type0-PDCCH CSS repetition, further check whether cross-SSB beam type0-PDCCH repetition can be used as a supplementary scheme to enhance the coverage of type0-PDCCH.

Proposal 4: The indication of type0-PDCCH CSS repetition is via a reserved bit in PBCH.

Proposal 5: For coverage enhancement of PDCCH CSS (other than type0 and type3), support intra-slot PDCCH repetition.

Proposal 6: The indication of PDCCH CSS repetition (other than type0 and type3) is via search space linkage for PDCCH CSS configured in SIB1.

Observation 2: Two PDSCH with Msg4 repetitions cannot enhance the coverage by 2.8 dB.

Proposal 7: For PDSCH with Msg4 repetition, the maximum repetition number is 4.

Proposal 8: For PDSCH with Msg4 repetition, support SIB1 configuring PDSCH with Msg4 repetition (Option 2) and DCI indicating UE specific repetition (Option 1). 

Proposal 9: For PDSCH with Msg4 repetition, 
SIB1 configures a repetition number of PDSCH with Msg4 and its associated RSRP threshold. 
UE reports its capability and request for PDSCH with Msg4 repetition (e.g., via Msg3 PUSCH), where the request is based on the comparison between UE’s measured RSRP and SIB1 configured RSRP threshold.

Proposal 10: For the indication of PDSCH with Msg4 repetition, consider the following alternatives on PDSCH with Msg4 scheduling DCI indicating the activation of PDSCH with Msg4 repetitions. 
Alt 1: New RNTI (e.g., TC-RNTI +1 mod )
Alt 2: Enhanced TDRA table with each TDRA entry associated with a repetition number
Alt 3: Calculated TBS of Msg4 larger than a TBS threshold
Alt 4: Re-interpreted MSB of MCS field.

Proposal 11: For PDSCH with Msg4 repetition, consider 
PDSCH with Msg4 initial transmission and repetition occur in consecutive slots
PDSCH with Msg4 repetition occupies the same time and frequency resources in a slot as PDSCH with Msg4 initial transmission
PDSCH with Msg4 repetition performs RV cycling.

Proposal 12: RAN1 to support PDSCH with SIB1 repetition with or without type0-PDCCH CSS repetition.

Proposal 13: For PDSCH with SIB1 repetition occurs without type0-PDCCH CSS repetition, support 
PDSCH with SIB1 initial transmission in the same slot as type0-PDCCH transmission.
PDSCH with SIB1 repetition occurs X =after the PDSCH with SIB1 initial transmission, where  being the maximum number of SSB beams allowed for a frequency band and M being configured in MIB.
RV cycling is applied for PDSCH with SIB1 repetition.

Proposal 14: For PDSCH with SIB1 repetition occurs together with type0-PDCCH CSS repetition, support 
PDSCH with SIB1 repetition are in the same slots as type0-PDCCH CSS repetition.
An additional PDSCH with SIB1 reception occurs X slots after the slot of type0-PDCCH CSS repetition, where .

Proposal 15: For the indication of PDSCH with SIB1 repetition, consider the following options: 
Option 1: Reserved bit in PBCH
Option 2: Reserved bit in scheduling DCI with CRC scrambled by SI-RNTI.

Proposal 16: For the default SSB periodicity extension and beam hopping, the radio frames for UE’s PDCCH monitoring in the type0-PDCCH CSS sets need to be modified, depending on the default SSB periodicity and the radio frames with SSB coverage. 

Proposal 17: If the uplink beam hopping is considered, the RACH occasion offset need to be modified, depending on the radio frame with SSB coverage. 

Proposal 18: For the default SSB periodicity extension and beam hopping, adjust the Msg2/Msg4/MsgB reception window such that they are within the duration with satellite beam coverage. 

Proposal 19: To avoid UE’s unnecessary downlink monitoring and uplink transmissions, the duration of downlink and uplink beam coverage for a beam footprint should be indicated by network. 

3GPP TSG RAN WG1 #120bis												  R1-2502695
Wuhan, China, April 7th – 11th, 2025
Agenda Item:	9.11.1
Source:	HONOR
Title:	Discussion on NR-NTN downlink coverage enhancement
Document for:	Discussion and Decision

Conclusions
In this contribution, we provide our views on NR-NTN downlink coverage enhancement with the following proposals.
Proposal 1: Using the spare 1 bit in MIB to enable PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero.
Proposal 2: For PDCCH repetition for Type0 PDCCH CSS set, option 2 that support repeated PDCCH candidates in the two slots n_0 and n_0+X associated with the same SSB index should be supported.
Proposal 3: Support option 3 that the repetition of PDSCH with SIB1 is indicated by the scheduling PDCCH.
Proposal 4: Using two consecutive slots to transmit repetitions of PDSCH with SIB1, the first slot used for initial transmission is the slot indicated by the DCI format 1_0 with CRC scrambled by SI-RNTI.  
Proposal 5: Support option 2 that Msg4 repetition is configured by SIB1.
Proposal 6: Use Msg1 to report the UE capability for DL coverage enhancement.  
Proposal 7: The information of UE capability for DL coverage enhancement can be shared by different DL channels, i.e. CSS PDCCH, PDSCH with SIB and PDSCH with Msg4.
Proposal 8: Support different power allocation for different SS/PBCH blocks.
Proposal 9: The CSI-RS power offset relative to specific SS/PBCH block should be considered. 
Proposal 10: The L1/L2 signaling should be considered to support dynamic and flexible power sharing between satellite beams or different satellite beam patterns/size. 
Proposal 11: Impacts on measurements should be studied when dynamic and flexible power sharing between satellite beams or different satellite beam patterns/size is introduced in NTN system.

3GPP TSG RAN WG1 Meeting #120bis	R1-2502716
Wuhan, China, April 7th – 11th, 2025

Agenda Item:	9.11.1
Source:	MediaTek Inc.
Title:	NR-NTN downlink coverage enhancement
Document for:	Discussion and Decision 


1 

Conclusion
In this contribution, the following proposals were made as follows:

Inter-slot PDCCH repetition for Type0 PDCCH CSS:
Observation 1: Option 1 has minimum impact on specifications and complexity.

Observation 2: It would be preferable to have a common solution with inter-slot PDCCH repetition for Type-0 PDCCH CSS (SIB1), Type-0A PDCCH CSS (other SIBs), Type-1 PDCCH CSS (Msg2, Msg3, Msg4), and Type-2 PDCCH CSS (paging).
Observation 3: PDCCH 1% BLER @ SNR = -6.3 dB  (gap = 1.7 dB with -8 dB target). PDCCH with 2 repetitions combined 1% BLER @ SNR = -8.9 dB (meet the -8 dB target)
Proposal 1: For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, support Option 1. 
Proposal 2: Support inter-slot repetition for Type-0A PDCCH CSS (other SIBs), Type-1 PDCCH CSS (Msg2, Msg3, Msg4), and Type-2 PDCCH CSS (paging).
Proposal 3: RAN1 to consider a maximum of 2 repetitions of inter-slot PDCCH repetition for Type0 PDCCH CSS. 

Intra-slot PDCCH repetition for Type3 PDCCH CSS:
Observation 4: The simplest way for intra-slot PDCCH repetition for Type-3 PDCCH CSS is to have   PDCCH repeated over contiguous symbols.
 Proposal 4: Support intra-slot repetition with contiguous symbols  for Type3 PDCCH CSS.

SIB1 enhancements:
Proposal 5: PDSCH repetition of SIB1 is transmitted within the same slot as the type0-CSS PDCCH repetition (Option 1).

Physical layer procedures for ON/OFF beams:
Observation 5: Whether a beam is wide or narrow to perform initial DL synchronization, SI acquisition, random access procedure and data transfer is transparent to the UE in existing specifications.
Observation 6: A UE can synchronize and perform random access on wide beam and be configured via RRC signalling to make measurement with NCD-SSB transmitted on narrow beams overlapped by a wide beam to re-direct UE to best narrow beam for data transfer with the existing specifications.
Proposal 6: Support enhancements for transmitting the DL common channels using a wider beam footprint and transmitting DL/UL dedicated channels (incl. PRACH) using a narrower beam footprint with the following options:
As determined by the UE based on its location and assisted information broadcast on SIB.
As configured via common signalling on SIB based on UE measurements on NCD-SSBs with SS/PBCH Block index linked to narrow beam configured on SIB. 

Discontinuous reception for paging:

Proposal 7: A necessary condition for UE to wake up during On duration of paging DRX cycle starting at time that coincides with an extended SSB transmission to monitor PDCCH Type-0 CSS (SIB1) and PDCCH Type-2 CSS (Paging) is that the PagingCycle is a multiple of extended SSB periodicities. 

8 

3GPP TSG RAN WG1 #120-bis                               R1-2502727
Wuhan, China, April 7th – 11th, 2025

Agenda item:	9.11.1
Source: 	CSCN
Title:	Discussion on downlink coverage enhancement for NR-NTN
Document for:	Discussion & Decision

Conclusions
In this contribution, we provide some views on downlink coverage enhancement for NR NTN scenarios. The proposals are summarized as following.
Proposal 1: SSB index should be associated with the ground beam footprint to ensure consistent synchronization and simplify mobility management for UEs.
Proposal 2: RAN1 to consider the beam hopping pattern, including dwell time and revisit time, and the UL beam hopping pattern should be considered in conjunction with the DL beam hopping pattern.
Proposal 3: The imbalanced user distribution of different beam footprints and DL/UL inter-beam interference should be considered for the beam hopping pattern design.
Proposal 4: Sufficiently sparser synchronization grids could be employed to decrease the cell search complexity. The impacts on specs could be studied in RAN4.
Proposal 5: The existing Type0-PDCCH CSS MO, RO, and PO need to be adjusted to adapt the extended SSB periodicity and beam hopping pattern, i.e., the dwell time and revisit time.
Proposal 6: If wide beams are used, minimizing the impact on specs should be carefully considered.
Observation 1: The supported number of Type0 PDCCH CSS repetitions should be determined before down-selecting the options for repetition indication.
Proposal 7: Prioritize Option 1 for PDSCH repetition of SIB1 to minimize signaling overhead and latency, and reuse the repetition configuration mechanism of the Type0-CSS PDCCH.

3GPP TSG RAN WG1 #120bis	R1-2502779
Wuhan, China, April 7th – 11nd, 2025

Source:	NTT DOCOMO, INC.
Title:	Discussion on DL coverage enhancement for NR-NTN
Agenda Item:	9.11.1
Document for: 	Discussion and Decision

Conclusion
In this contribution, we discussed DL coverage enhancement for NR-NTN. Observations/Proposals are summarized as following: 
Proposal 1:
For PDCCH CSS type 0, with respect to time resource of PDCCH repetition,
Support Option 1 (n0 and n0+1), without specifying explicit M value restrictions.
Note that at least the following is applicable.
Any index of table 13-11 in 38.213 for a single SSB index within a cell.
Index 9 of table 13-11 in 38.213 for more than one SSB index within a cell.
Proposal 2:
For PDCCH CSS type 0, with respect to enabling of PDCCH repetition,
Support either Option 1 (the spare bit in MIB) or Option 2 (reserved bit(s) in PBCH).
Proposal 3:
For PDCCH CSS type 0A/0B/1/1A/2/2A, 
Support intra-slot repetition as in R17 M-TRP PDCCH repetition.
Two search space configurations with search space linking are provided in PDCCH-ConfigCommon via SIB or UE dedicated signaling.
Search space sets i and j are associated with CORESETs i and j, respectively.
CORESETs i and j have the same configuration parameters.
Observation 1:
R17 PDCCH repetition is assumed with the following two decoding behavior, which may not be reasonable in R19 NTN.
A: Two blind decoding (Decode of the first PDCCH + Decode of the second PDCCH)
B: Three blind decoding (Decode of the first PDCCH + Decode of the second PDCCH + Decode of a soft-combined PDCCH)
Proposal 4:
For repetitions of PDCCH CSS type 3 and USS,
Support ‘1’ as required number of BDs for the two PDCCH candidates.
Specify BD counting rule for this support of ‘1’, in TS 38.213.
Observation 2:
R17 PDCCH repetition can be applied to both single-TRP scenario and multi-TRP scenario.
UE capability signaling for R17 PDCCH repetition does not have any differentiation between single-TRP scenario and multi-TRP scenario, which implies that UE reporting the capability signaling as ‘support’ must support both scenarios.
Proposal 5:
For repetitions of PDCCH CSS type 3 and USS,
Define UE capability signaling of PDCCH repetition in case of single-TRP scenario.
When UE reports this capability, required number of BDs for the two PDCCH candidates = 1.
Detailed FG is discussed in UE feature session.
Proposal 6:
For SIB1 PDSCH repetition, separately discuss slot determination perspective and enabling perspective.
Proposal 7:
For SIB1 PDSCH repetition,
With respect to slot determination, slots n0 and n0+1 are used (Option 1).
With respect to enabling, support indication via the scheduling DCI (Option 3).
1 bit of 15 reserved bits is used for the indication.
Proposal 8:
For SIB1 PDSCH repetition, RAN1 to discuss how the repetitions are efficiently transmitted in consideration of beam hopping.
E.g., repetitions w/ different length per repetition.
Proposal 9:
For Msg4 PDSCH repetition, repetition factor is only 2.
Proposal 10:
For Msg4 PDSCH repetition,
Enabling/disabling configuration is provided via SIB.
The scheduling DCI indicates to enable the repetition by 1 bit of TDRA field or MCS field.
Observation 3:
For Msg4 PDSCH repetition, further PRACH resource partitioning or further consumption of Msg3 LCID codepoints may not be desirable.
Observation 4:
For Msg4 PDSCH repetition, when Msg4 PDSDCH repetition is applied and if PUCCH resource for Msg4 HARQ-ACK is determined based on the first reception of Msg4 repetitions, the feedback timing is aligned regardless of whether the scheduled UE is capable of Msg4 PDSCH repetition or not.
Proposal 11:
For Msg4 PDSCH repetition, RAN1 to discuss the following alternatives for UE capability/request:
Alt 1: Report support of Msg4 PDSCH repetition via PRACH or Msg3.
Alt 2: Slot offset K1 for HARQ feedback corresponding to Msg4 RX is counted from the first repetition.
UE capability/request is not transmitted to gNB via PRACH or Msg3.
Proposal 12:
Not support RO enhancements to adapt to the extended SSB periodicity of 160 ms.


Agreements
Agreement
For DL coverage study, consider the following additional reference satellite parameters scenarios for LEO600km Set1 in FR1 (i.e., S-band), referred to as Set1-1 FR1, Set1-2 FR1 and Set1-3 FR1:




Note: RAN1 will aim to identify necessary enhancements for these scenarios in the study phase. At the end of the study phase, RAN1 will further discuss whether the potential enhancements will be specified within Rel-19 framework.

Agreement
For DL coverage study at system level, consider the following additional reference satellite payload parameters for LEO600km in FR2 (i.e., Ka-band):


Agreement
Adopt the following phased array antenna parameters for LEO 600km in FR1:

Agreement
RAN1 to consider the following performance metrics for DL Coverage enhancement evaluation at system level:
At least:
CDF of the received SINR
The dwell time and revisit time interval for each beam illumination across the coverage
Periodicity of common control channels (e.g. SSB, CORESET0/SIB1, SIB19) and corresponding coverage ratio

Other metrics may be reported such as
CDF of the cell throughput
CDF of user perceived throughput (UPT)
CDF of Latency
Ratio of mean served cell throughput and offered cell throughput, denoted by 𝜌 (refer to TR36.889)

For system level study based on analytical evaluation:
N1 beam footprints are in state “off”
These beam footprints are not served by any signal (no satellite service in this area)
N2 beam footprints are in state “common messages only”
These beam footprints do not have any active user traffic, and are served the necessary information for cell discovery and initial access.
Optionally, companies may consider user arrival (e.g. RACH access) in this type of cell, and should describe how this is taken into account in the analytical evaluation
N3 beam footprints are in state “active traffic” 
These beam footprints have X active (e.g. VoNR) users each.
These beam footprints are also served the necessary information for cell discovery and initial access
N1 + N2 + N3 = “Total number of beam footprints “ 
N1, N2, N3, X are to be reported by companies.
Resource utilization obtained under the assumptions above is to be reported by companies.
Other assumptions made in the evaluation are to be reported by companies, e.g. power sharing scheme, beam hopping scheme, etc.

Agreement
For NR NTN Rel-19 DL coverage evaluation, UE characteristics for handheld terminals in Table 6.1.1.1-3 in TR 38.821 can be reused, with the following:
-5.5 dBi antenna gain is assumed
at least 2Rx are considered at the UE
4Rx can be optionally considered and reported 
Note: Redcap device is not considered in the scope of DL coverage study

Agreement
The following traffic models are considered for system level evaluation of DL coverage:
FTP3: as in Table 6.1.1.1-7 of TR 38.821: 0.5MB as packet size, 200ms as mean inter-arrival time 
FTP3 IM: 0.1MB as packet size, 2s as mean inter-arrival time 
VoIP can be considered in the evaluation. 

It is up to company report which traffic model is used among the discussed traffic models in their evaluations.
Other models may be used as well, and parameter (e.g. packet size and arrival rate) adjustment can be optionally considered and reported.

Agreement
For NR NTN Rel-19 DL coverage evaluation, Beam layout defined in Table 6.1.1.1-4 in TR 38.821 can be reused.
Using other beam layouts is not precluded, and should be reported by companies

Agreement
For NR NTN Rel-19 DL coverage evaluation, a value of beam steering latency equal to 0 at least if phase array antenna is assumed.
Values different from 0 can be optionally reported

Agreement
DL coverage is evaluated at link level with the following considerations:
NGSO at LEO-600 operating in FR1 is considered in priority
Additional satellite payload parameters defined for system level evaluation are used
FFS: Antenna gain reduction due to steering loss can be considered 

Agreement
For the evaluation of NTN downlink coverage at link level, reuse the target data rate from Rel-18 NTN Coverage enhancements:
For VoIP: AMR 4.75 kbps (TBS of 184 bits without CRC in physical layer) with 20 ms data arriving interval 
For data rate service: both 3 kbps and 1Mbps can be considered
Companies can also use the data rates corresponding to the traffic types used for system level evaluations

Agreement
For link-level study, downlink coverage performance in NR NTN is evaluated according to the following steps.
Step 1: CNR is calculated as defined in 6.1.3.1 of TR 38.821
Step 2: Required SNR of target service is evaluated by LLS
Step 3: The CNR and the required SNR are compared

Agreement
For link-level study, for NR NTN DL coverage enhancement, the following channels/signals can be considered for evaluations:
PDSCH for VoIP
PDSCH for low data rate service
PDSCH Msg.2
PDSCH Msg.4
PDSCH carry SIB, e.g., SIB1, SIB 19
PDSCH for paging
PDCCH
Broadcast PDCCH (e.g. PDCCH of Msg.2, paging)
SSB
Note: RAN1 will aim to identify necessary link-level enhancements for these channels in the study phase. At the end of the study phase, RAN1 will further discuss whether the potential link-level enhancements will be specified within Rel-19 framework.

Agreement
For DL coverage performance evaluation, the following are assumed for all channels/signals
Channel model/Delay spread:
Channel model as in Table 6.1.2-4 of TR38.821, NTN-TDL-C (LOS)
Evaluation scenario:
Rural (LOS)
Channel estimation: Realistic estimation:
Companies are encouraged to report channel estimation method.
SCS:
15 kHz only
UE speed: 3 km/h
Frequency drift: TBD
Frequency offset: 0.1 ppm

Agreement
For link budget calculation, parameters in the following table are assumed:

Agreement
For coverage evaluation of PDCCH in NR NTN, the following table is assumed:

Agreement
For coverage evaluation of PDSCH in NR NTN, the following table is assumed:

Agreement
Antenna gain reduction due to steering loss is not considered in the link level evaluation.
Note: This is aligned with the assumptions made in Rel-18 UL coverage enhancement

Observation
The CNRs for the satellite payload parameters Set 1-1, Set 1-2 and Set 1-3 are equal to -1.9 dB, -1.9 dB and -9.9 dB respectively.

Agreement
Confirm the Satellite phased-array antenna parameters for LEO 600km in FR1 defined in RAN1#116.
Al least the above model is considered for SLS to ease the alignment between evaluation results. The model below can be optionally considered:
Note 1: The maximum antenna gain is determined by considering an overall array efficiency [of 50%.] 

Agreement
For coverage evaluation of PDSCH in NR NTN, the following payload sizes for PDSCH are assumed:
Note: At least the above values are simulated and reported. Other values can be considered.
Note: the values above are not the TBS.

Agreement
For DL coverage study at system level, it is up to companies to report the following parameters for LEO600km Set1-1 FR2:

Agreement
For coverage performance evaluation of DL channels/signals before the SIB19 acquisition, the maximum Doppler frequency drift is assumed to be equal to 0.27 ppm/s based on TR 38.821.

Observation
Based on LLS results on PDCCH coverage evaluation collected from different sources:
It is observed that the required SNR for PDCCH is in average equal to -6dB (17 sources)
With parameter LEO600km Set1-1 FR1 and 1-2 FR1: 
17 sources observed that there is no coverage gap with Set1-1/1-2 FR1.
The coverage margin is around 4 dB compared to CNR of -1.9 dB.
With parameter LEO600km Set1-3 FR1: 
15 sources observed that there is a PDCCH coverage gap of 3.9dB in average compared to CNR of -9.9 dB.
Note: the results above are obtained independently from the performance of other channels or signals, and it doesn’t imply the successful reception for other channels or signals before or after the detection of PDCCH.

Observation
Based on LLS results on PDSCH Msg2 coverage evaluation collected from different sources:
It is observed that the required SNR for PDSCH carrying Msg2 is in average equal to – 10.9 dB (14 sources)
With parameter LEO600km Set1-1 FR1 and 1-2 FR1: 
14 sources observed that there is no coverage gap for PDSCH with Msg2: 
The coverage margin is around 9 dB compared to CNR of -1.9 dB  
With parameter LEO600km Set1-3 FR1: 
12 sources observed that there is no coverage gap for PDSCH with Msg2: 
The coverage margin is around 1 dB on average compared to CNR of -9.9 dB
Note: the results above are obtained independently from the performance of other channels or signals, and it doesn’t imply the successful reception for other channels or signals before or after the detection of PDSCH Msg2.

Observation
Based on LLS results on PDSCH Msg4 coverage evaluation collected from different sources:
It is observed that the required SNR for PDSCH carrying Msg4 is in average equal to – 5.2 dB (14 sources)
With parameter LEO600km Set1-1 FR1 and 1-2 FR1: 
14 sources observed that there is no coverage gap for PDSCH with Msg4: 
The coverage margin is around 3.3 dB on average compared to CNR of -1.9 dB
With parameter LEO600km Set1-3 FR1: 
11 sources observed that there is a coverage gap for PDSCH with Msg4: 
The coverage gap is around 4.7 dB on average compared to CNR of -9.9 dB
1 source observed that there is no coverage gap for PDSCH with Msg4 with a coverage margin of 0.3 dB compared to CNR of -9.9 dB
Note: the results above are obtained independently from the performance of other channels or signals, and it doesn’t imply the successful reception for other channels or signals before or after the detection of PDSCH Msg4.

Observation
Based on LLS results on PDSCH SIB1 coverage evaluation collected from different sources:
For PDSCH carrying SIB1 option 1 (with a payload size of 800bits) it is observed that the required SNR is in average equal to – 5.8 dB (14 sources)
For PDSCH carrying SIB1 option 2 (with a payload size of 1280bits) it is observed that the required SNR is in average equal to – 3.4 dB (12 sources)
With parameter LEO600km Set1-1 FR1 and 1-2FR1: 
14 sources observed that there is no coverage gap for PDSCH with SIB1 option 1: 
The coverage margin is around 3.9 dB on average compared to CNR of -1.9 dB
12 sources observed that there is no coverage gap for PDSCH with SIB1 option 2: 
The coverage margin is around 1.5 dB on average compared to CNR of -1.9 dB

With parameter LEO600km Set1-3 FR1: 
11 sources observed that there is a coverage gap for PDSCH with SIB1 option 1: 
The coverage gap is around 4.1 dB on average compared to CNR of -9.9 dB
1 source observed that there is no coverage gap for PDSCH with SIB1 option 1: 
The coverage margin is 3.4 dB compared to CNR of -9.9 dB
10 sources observed that there is a coverage gap for PDSCH with SIB1 option 2: 
The coverage gap is around 6.5 dB on average compared to CNR of -9.9 dB
Note: some results assumed SIB1 combination (where SIB1 is repeated within 160 ms) and some results assumed no SIB1 combination
Note: the results above are obtained independently from the performance of other channels or signals, and it doesn’t imply the successful reception for other channels or signals before or after the detection of PDSCH carrying SIB1.

Observation
Based on LLS results on PDSCH SIB19 coverage evaluation collected from different sources:
It is observed that the required SNR for PDSCH carrying SIB19 is in average equal to – 6.9 dB (14 sources)
With parameter LEO600km Set1-1 FR1 and 1-2 FR1: 
12 sources observed that there is no coverage gap for PDSCH with SIB19: 
The coverage margin is around 4.2 dB on average compared to CNR of -1.9 dB  
With parameter LEO600km Set1-3 FR1: 
10 sources observed that there is a coverage gap for PDSCH with SIB19: 
The coverage gap is around 3.5 dB on average compared to CNR of -9.9 dB
Note: all the results above assumed no SIB19 combination
Note: the results above are obtained independently from the performance of other channels or signals, and it doesn’t imply the successful reception for other channels or signals before or after the detection of PDSCH carrying SIB19.

Observation
Based on the results of DL coverage ratio evaluation at system level collected from 7 sources for all the three LEO600km satellite parameter sets where the beam footprint diameter is 50 km:
For Set 1-1/1-3, the coverage ratio can be improved from 10% to 100% if the SSB periodicity is increased from 20ms to 80ms and beam hopping is applied
For Set 1-2, the coverage ratio can be improved from 1.5% to 96.8% if the SSB periodicity is increased from 20ms to 320ms and beam hopping is applied.
Note: coverage ratio is N2+N3/ total beam footprints
Note: the baseline assumes no beam hopping. TDM between SIB1 and SIB19 is assumed in those results, following current specs.
Based on the results of DL coverage ratio evaluation at system level collected from 3 sources for a deployment scenario implementing wide beam footprint:
1 source reports that with a deployment of wide beam covering 4 narrow (of 50km size) beams, which means Set 1-2 FR1 with additional EIRP reduction of 6dB, using SSB periodicity of 80 ms can provide coverage ratio of 96.8%, and Set 1-1/1-3 FR1 with additional EIRP reduction of 6dB, SSB periodicity of 80 ms can provide coverage of 100%.
1 source observed that for Set 1-1, 1-2 and 1-3, the coverage ratio can be improved from 1.5% to 100% using the legacy default SSB periodicity of 20ms during initial access, by choosing a wide beam footprint with beam footprint sizes of 84 km and 56 km respectively. 
Note: the PDCCH and the PDSCH for SIB19 is assumed to be transmitted within 2 OFDM symbols and 5 MHz bandwidth. the PDSCH for SIB1 is assumed to be transmitted within 3 OFDM symbols and 5 MHz bandwidth. This assumes no SIB1 and SIB19 transmission in N2 beam footprints. This assumes non-aligned SFN timing across different beams.
1 source observed, for Set 1-1 with increased beam size, that the legacy SSB periodicity of 20ms during initial access is usable with NTN beam hopping, by choosing a deployment scenario implementing wide beam footprint with beam footprint sizes of 70.7 km and 86.6 km, leading to a total of 529 and 353 beam footprints within the satellite coverage area, respectively, and the coverage ratio is 80% and 90%, respectively, and a ratio of simultaneously active beam footprints to the total number of beam foot prints equal to 20% and 30%. 
Note: Beam footprint size is increased by increasing only the adjacent beam spacing without increasing the 3dB beamwidth.
Note: RAN1 will further investigate the impact of SSB periodicity extension
Note: Any needed clarification “SSB channel enhancement is not considered” in the WID is up to RAN plenary
Note: RAN1 will further investigate the impact of wider beam of SSB and/or other channels on performance (e.g. link budget, capacity...)

Observation
Based on LLS results on PDSCH for VoIP coverage evaluation collected from different sources:
It is observed that the required SNR for PDSCH for VoIP is in average equal to – 11 dB (11 sources)
With parameter LEO600km Set1-1 and 1-2 FR1: 
When PDSCH repetition is enabled, 11 sources observed that there is no coverage gap for VoIP: 
The coverage margin is around 9.1 dB on average, compared to CNR of -1.9 dB   
With parameter LEO600km Set1-3 FR1: 
When PDSCH repetition is enabled, 9 sources observed that there is no coverage gap for VoIP: 
The coverage margin is around 2.3 dB on average, compared to CNR of -9.9 dB
1 source observed that even with 8 PDSCH repetitions there is a coverage gap of 1.5 dB compared to CNR of -9.9 dB
Note: the results above are obtained independently from the performance of other channels or signals, and it doesn’t imply the successful reception for other channels or signals before or after the detection of PDSCH for VoIP.

Observation
Based on LLS results on PDSCH 3kbps coverage evaluation collected from different sources:
It is observed that the required SNR for PDSCH for low data rate is in average equal to – 11 dB (8 sources)
With parameter LEO600km Set1-1 FR1 and 1-2 FR1: 
When PDSCH repetition is enabled, 8 sources observed that there is no coverage gap for PDSCH with 3kbp: 
The coverage margin is around 9.1 dB on average, compared to CNR of -1.9 dB   
With parameter LEO600km Set1-3 FR1: 
When PDSCH repetition is enabled, 6 sources observed that there is no coverage gap for PDSCH with 3kbp: 
The coverage margin is around 1.6 dB on average, compared to CNR of -9.9 dB
Note: the results above are obtained independently from the performance of other channels or signals, and it doesn’t imply the successful reception for other channels or signals before or after the detection of PDSCH 3kbps.

Observation
Based on LLS results on PDSCH 1Mbps coverage evaluation collected from different sources:
It is observed that the required SNR for PDSCH with 1Mbps data rate is in average equal to – 4.1 dB (7 sources)
With parameter LEO600km Set1-1 FR1 and 1-2 FR1: 
7 sources observed that there is no coverage gap for PDSCH with 1Mbps: 
The coverage margin is around 2.2 dB on average, compared to CNR of -1.9 dB   
With parameter LEO600km Set1-3 FR1: 
5 sources observed that, there is a coverage gap for PDSCH with 1Mbps: 
The coverage gap is around 5.5 dB on average, compared to CNR of -9.9 dB
Note: the results above are obtained independently from the performance of other channels or signals, and it doesn’t imply the successful reception for other channels or signals before or after the detection of PDSCH 1Mbps.

Observation
Based on the results of DL coverage evaluation at system level collected from different sources, it is observed that extending the default value of SSB periodicity (different from 20ms) in NTN with LEO600km satellite parameter sets where the beam footprint diameter is 50 km, is beneficial in terms of reduction of common control channel overhead, when targeting a full coverage of 1058 beam footprints: 
With Set 1-1 FR1 and Set 1-3 FR1, the common messages (SSB, SIB1) overhead is around 40% assuming 5 MHz BW when SSB/SIB1 periodicity of 20ms is in use, this overhead ratio could be reduced to less than 14% when 160ms SSB/SIB1 periodicity is used.
With Set 1-2 FR1, the common message (SSB, SIB1) overhead is greater than 100% assuming 5 MHz BW when SSB/SIB1 periodicity of 20ms is in use, this overhead could be reduced to around 25.8% when 640ms SSB/SIB1 periodicity is used.
Note: the overhead of SIB19 was included in some of the results
Note: an observation when SSB/SIB1 periodicity is 320 ms will be discussed and added to the observation

Agreement
As part of the NTN DL coverage enhancements at both system level and link level, RAN1 to consider:
Extending the periodicity of the half frames with SS/PBCH blocks assumed by UE during initial access. 
Default value[s] with extended periodicity assumed by NTN UE for initial access can be:
One [or more] values from the list {40ms, 80 ms, 160 ms, 320ms, 640ms} 
Potential enhancements for transmitting the DL common channels using a wider beam footprint, while DL/UL dedicated channels (incl. PRACH) may be transmitted using a narrower beam footprint
Link-level enhancements for the following channels:
PDCCH 
PDSCH with Msg 4 
PDSCH with SIB1/SIB19.
Note: link-level enhancements for PDSCH with SIB1/SIB19 may be applicable to other SIBs, without additional specification impact.
Note: the above does not imply that all the channels above will be enhanced, but all of them should be considered based on this agreement

Agreement
For NR NTN, support extended periodicity of the half frames with SS/PBCH blocks assumed by UE during initial access. 
The maximum of the additional default value (apart from the existing 20ms value) is at least 160 ms.
FFS: whether 320ms can be supported as the maximum of the additional default value instead of or in addition to 160ms

Agreement
Support PDCCH CSS Link level enhancement in Rel-19 for all CSS types except type 3. 
The following techniques are for further study:
PDCCH repetition, including:
Option 1: Intra-slot PDCCH repetition
Option 2: Inter-slot PDCCH repetition
CORESET length (i.e. number of OFDM symbols) extension 
DCI format optimization (e.g. size reduction, etc)
Note: the same technique is intended to apply to all search space types targeted for link level enhancements
For the above techniques, at least the following aspects should be discussed for the relevant candidate techniques:
Configuration
Backward compatibility and UE behaviour of legacy UE
Linked Search Space
Blocking probability
DCI format size budget
Resource overhead
Impact on CORESET0
Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.
FFS: whether to apply the selected solution to PDCCH CSS type3 and PDCCH USS

Agreement
For PDSCH with Msg4 Link level enhancement:
Continue studying PDSCH repetition
Further discuss the specification impact for at least the following:
Procedure and signaling
Repetition factor
Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.

Agreement
For PDSCH with Msg4 Link level enhancement:
Support PDSCH repetition
FFS: signalling design including number of repetitions
FFS: impact on UE capability
Note: the target coverage enhancement to bridge the gap with respect to single Msg4 transmission is 2.8 dB
Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.

Observation
Backward compatibility for legacy UEs (i.e. Rel-17 and Rel-18 UEs) assuming a default SSB periodicity of 20ms is not guaranteed when SS/PBCH blocks periodicity is larger than 20ms within the cell used for initial frequency scan.
Legacy UEs (i.e. Rel-17 and Rel-18 UEs) are not expected to be able to camp on a cell with SS/PBCH blocks periodicity larger than 160 ms.

Agreement
For link level enhancement of PDSCH with SIB1:
Support PDSCH repetitions within 20 ms duration
The number of repetitions is fixed to 2 repetitions 
Further discuss the specification impact for at least the following:
Procedure and signaling (enabling repetitions, associated time resource determination, etc.)
Note 1: without the above PDSCH repetitions, the coverage gap is 2.2 dB to 4.6 dB depending on SIB1 size.
Note 2: Focus on coverage enhancement for set 1-3 with a target CNR of -8 dB for NR NTN DL coverage enhancements at link level.
Note 3: the above is not related to multiple SIB1 transmissions across 20 ms periodicities of SSB, which may not be available when the SSB periodicity is 160 ms or larger (if supported) depending on the SSB and CORESET multiplexing pattern.

Agreement
For PDCCH CSS (except Type-3) link level enhancements, support only PDCCH repetition for NTN.
FFS: intra-slot and/or inter-slot

Agreement
For NR NTN, support extended periodicity of the half frames with SS/PBCH blocks assumed by UE during initial access. 
The additional default value assumed by UE during initial access (apart from the existing 20ms value) is 160 ms.

Agreement
Support only inter-slot repetition for Type0 PDCCH CSS.

Agreement
For Msg4 PDSCH repetition support, RAN1 to consider:
Option 1: UE specific repetition indication via DCI
Option 2: Msg4 repetition is configured by SIB1
Option 3: Msg4 PDSCH repetition is implicitly determined by SIB1 PDSCH repetition 

Agreement
At least for enabling PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, RAN1 to consider the following options
Option 1: Using the spare 1 bit in MIB
Option 2: Using reserved bit(s) in PBCH payload
Option 3: Using codepoint(s) in PBCH payload
Option 4: UE blind decoding without signaling from the network during initial access

Agreement
For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, consider the following:
Option 1: Support repeated PDCCH candidates in the two consecutive slots   and  associated with the same SSB index (  as defined in section 13 of TS 38.213)
Repeated PDCCH candidates share the same aggregation level (AL), coded bits and same candidate index
FFS: Details including how the two PDCCH candidates are counted toward the BD limits
Note: with option 1, if the network repeats the Type 0 PDCCH across two consecutive slots, a legacy UE might decode the PDCCH and associated PDSCH in one slot and skip PDCCH monitoring in the other slot. 
FFS: whether/how option 1 can be applicable for M=1 and M= ½
Option 2: Support repeated PDCCH candidates in the two slots   and  [or  and  ] associated with the same SSB index (  as defined in section 13 of TS 38.213)
Value of X>1, predefined or configured
FFS: Value of X 
Repeated PDCCH candidates share the same aggregation level (AL), coded bits and same candidate index
FFS: Backward compatibility to legacy UE
Option 3: 
The PDCCH candidates in slots n0 associated respectively with different SSB indexes are repetitions of each other and share the same aggregation level, coded bits and same candidate index
For M=1/2 and M=1, the repeated PDCCH candidates in two consecutive slots associated with different SSB indexes;
For M=2, the PDCCH candidates in slots n0+1 associated respectively with different SSB indexes are repetitions of each other and share the same aggregation level, coded bits and same candidate index
Option 4: Option 2 with cross SSB beam repetition support
The PDCCH candidates in slots n0 associated respectively with different SSB indexes are repetitions of each other and share the same aggregation level, coded bits and same candidate index

Agreement
For SIB1 link level enhancement, RAN1 to consider the following options:
Option 1: PDSCH repetition of SIB1 is transmitted within the same slot as the type0-CSS PDCCH repetition.
UE supporting SIB1 PDSCH coverage enhancement assumes that the PDCCH and associated PDSCH to be repeated in both slots where the corresponding PDCCHs are transmitted.
Each PDSCH SIB1 repetition is within the same slot of each PDCCH candidate for scheduling DCI
The two associated PDSCHs have the same RV
Option 2: Option 1 and an additional PDSCH with SIB1 repetition can occur after the slot of type0-PDCCH CSS repetition.
FFS: How to schedule the SIB1 repetition
Option 3: The repetition of PDSCH with SIB1 is indicated by the scheduling PDCCH
PDSCH is repeated in two slots
Note: Backward compatibility should be maintained

3GPP TSG RAN WG1 #120bis						    R1- 2502815
Wuhan, China, April 7th – 11th, 2025
Agenda Item:	9.11.1
Source: 	LG Electronics
Title: 	Discussion on NR-NTN downlink coverage enhancement
Document for:	Discussion and decision

Conclusions
In this contribution, we discussed DL coverage enhancement for NR NTN. Based on the above discussion, our observations and proposals are given as follows:
Observation 1: RAN1 haven’t discuss the necessity of the limited active UL beam ratio or the details on the active UL beam period or patterns. Moreover, it is understood that the active UL beam issue is out of scope of the WI. 
Observation 2: If majority companies want to discuss the necessity of the enhancements to optimize RO configuration for 160msec default SSB periodicity, RAN1 should firstly discuss the details of the active UL beam period and patterns. 
Observation 3: If MIB or PBCH indication is introduced for enabling PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, the spare bit or the reserved bit(s) could be re-interpreted only for the NTN access. 
Observation 4: If any network signaling is not introduced for enabling PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, the total number of PDCCH candidates in Type0-CSS is not increased compared to the case when the Type0-CSS PDCCH repetition is not enabled. 
Observation 5: According to Set 1-2, it would be a typical scenario that a single SSB is used in a cell or a beam footprint to guarantee the limited active DL beam ratio. 
Observation 6: Since the reserved bit fields of the DCI format 1_0 for SIB1 PDSCH scheduling are not always fixed to 0, the UE and gNB can have different understanding on whether the SIB1 PDSCH repetition is enabled or not. To avoid this problem, MIB or PBCH needs to indicate whether the SIB1 PDSCH repetition is enabled or not. 

Proposal 1: RAN1 does not pursue a specific enhancement for Type0-CSS periodicity for the 160msec of the default SSB periodicity. 
Proposal 2: At least for enabling PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, down-select one of followings:
Option 1: Using the spare 1 bit in MIB
Option 2: Using reserved bit(s) in PBCH payload
Option 4: UE blind decoding without signaling from the network during initial access
The maximum total number of PDCCH candidates for Type0-CSS is not increased compared to the case where PDCCH repetition is not enabled. 
Proposal 3: For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, support Option 1 with following changes:
Option 1: Support repeated PDCCH candidates in the two consecutive slots   and  associated with the same SSB index (  as defined in section 13 of TS 38.213)
Repeated PDCCH candidates share the same aggregation level (AL), coded bits and same candidate index
UE expects that the repeated PDCCH candidates for the same DCI transmission are associated with the same SSB index in the perspective of the RX spatial information
Proposal 4: For PDCCH repetition for CSS other than Type0-CSS configured with the search space ID 0, reuse the same PDCCH repetition mechanism for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1.
Proposal 5: For PDCCH repetition for CSS other than Type0-CSS configured with the non-zero search space ID, Proposal 5: For Type0-CSS of searchSpaceZero not configured within MIB pdcch-ConfigSIB1, PDCCH repetition is not supported in Rel-19 NTN WI. 
Proposal 6: For Type0-CSS of searchSpaceZero not configured within MIB pdcch-ConfigSIB1, PDCCH repetition is not supported in Rel-19 NTN WI. 
Proposal 7: SIB1 PDSCH repetition is automatically enabled when PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1 is enabled. 
Proposal 8: For SIB1 PDSCH enhancement in Rel-19 NR NTN, 
Option 1: PDSCH repetition of SIB1 is transmitted within the same slot as the Type0-CSS PDCCH repetition.
UE supporting SIB1 PDSCH coverage enhancement assumes that the PDCCH and associated PDSCH to be repeated in both slots where the corresponding PDCCHs are transmitted.
Each PDSCH SIB1 repetition is within the same slot of each PDCCH candidate for scheduling DCI
The two associated PDSCHs have the same RV
Proposal 9: For Msg4 PDSCH enhancement in Rel-19 NR NTN, PDSCH-ConfigCommon provided by SIB1 is updated to include pdsch-TimeDomainAllocationList-r16. 

3GPP TSG RAN WG1 #120bis		R1-2502822
Wuhan, China, April 7th – 11th, 2025
Agenda Item:	9.11.1
Source:	Lenovo
Title:	Discussion on downlink coverage enhancement for NR NTN
Document for:	Discussion

Conclusion
In this contribution, we discussed the issues related to DL coverage enhancement for NR NTN, and our observations and proposals are as following:
Observation 1: Impact to cell identification, time/frequency synchronization due to larger default SSB periodicity can be alleviated by pre-configuration of SSB time resource and satellite ephemeris.
Observation 2: System information reception periodicity, system information modification period, paging monitoring periodicity, RACH occasion periodicity will also be impacted by the increased default SSB periodicity.
Observation 3: Wider beams for common channel signalling and narrow beams for dedicated channels may be used to provide full DL coverage in scenarios, where extended periodicity of 160ms cannot provide full coverage.
Observation 4: Association between a wide beam and several narrow beams may be exploited to have a low latency beam refinement procedure for the selection of best narrow spatial filter from the set of narrow beams within a wider beam.
Proposal 1: Support a time domain offset associated with a geographical area for PRACH time domain resource determination.
Proposal 2: For relationship among cell id, geographical area id, satellite beam, SSB, each satellite beam is associated with a geographical area id, multiple geographical area can be associated with a same cell id, and each satellite beam/geographical area can be associated with a single SSB time position/SSB index.
Proposal 3: SSB time domain position and SSB index should be configured to UE in a geographical area for geographical area identification.
Proposal 4: Support use of wider beam for common channel signalling and the use of narrow beams for UL/DL dedicated channels as an alternative to SSB periodicity extension.
Proposal 5: RAN1 to further study at least the following methods to select a narrow beam within a wider beam;
Repeated PRACH transmission over extended duration
Use of reference locations within the coverage of a wider beam
Association of a set of reference signals to narrow beams within the coverage of a wider beam
Proposal 6: Consider time resource division between wide beam and narrow beam.
Proposal 7: Geographical area identification for narrow beam can consider both wide beam index and narrow beam index.
Proposal 8: Consider beam index and power value indication for spatial/power domain beam adaptation in NR NTN.
Proposal 9: Consider satellite beam level DTX/DRX.
Proposal 10: RAN1 to define UE behaviors in off status of a satellite beam.
Proposal 11: Consider the impact of large propagation delay and dynamic DL Tx power change in addition to on-off pattern indication in R19 NR NTN.
Proposal 12: For type 0 PDCCH repetition, the time domain offset of PDCCH repetitions depends on value M.
Proposal 13: Both inter-slot and intra-slot PDCCH repetition can be supported considering additional time resource for repetition of PDCCH configured by SIB1 and configured by MIB.
Proposal 14: For Msg1 PDSCH repetition, support the case that the first PDSCH is after the repeated PDCCH.
Proposal 15: Msg4 PDSCH repetition factor indication can consider similar way as msg 4 PUCCH repetition factor indication.

3GPP TSG RAN WG1 #120bis			R1-2502854
Wuhan, China, April 7th – 11th, 2025

Agenda item:	9.11.1
Source: 	Qualcomm Incorporated
Title: 	Downlink coverage enhancement for NR NTN
Document for:	Discussion/Decision

Summary
In this contribution, we have proposed solutions for link level enhancements for PDCCH from CSS, SIB1 PDSCH and msg4 PDSCH. We have also proposed several mechanisms to better support extended SSB periodicities during initial access. Our proposals and observations are listed below: 
Proposal 1: For PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, support option 1 as below:
Option 1: Support repeated PDCCH candidates in the two consecutive slots   and  associated with the same SSB index (  as defined in section 13 of TS 38.213)
Repeated PDCCH candidates share the same aggregation level (AL), coded bits and same candidate index
FFS: Details including how the two PDCCH candidates are counted toward the BD limits
Note: with option 1, if the network repeats the Type 0 PDCCH across two consecutive slots, a legacy UE might decode the PDCCH and associated PDSCH in one slot and skip PDCCH monitoring in the other slot. 

Proposal 2: For SIB1 link level enhancement, support option 1 as below:
Option 1: PDSCH repetition of SIB1 is transmitted within the same slot as the type0-CSS PDCCH repetition.
UE supporting SIB1 PDSCH coverage enhancement assumes that the PDCCH and associated PDSCH to be repeated in both slots where the corresponding PDCCHs are transmitted.
Each PDSCH SIB1 repetition is within the same slot of each PDCCH candidate for scheduling DCI
The two associated PDSCHs have the same RV
Proposal 2: For PDCCH in CSS other than Type 3 and Type 0, supports non-overlapping CORSET repetition of N times within a slot where the N repetitions of a PDCCH are transmitted in the N CORSETs using the same aggregation level and the same candidate index.
FFS: the value of N.

Observation 1: For backward compatibility, indication of PDCCH repetition for Type0 PDCCH CSS in MIB or PBCH payload must be static, i.e., constant over time.
Proposal 3: for enabling PDCCH repetition for Type0 PDCCH CSS of searchSpaceZero configured within MIB pdcch-ConfigSIB1, support Option4:
Option 4: UE blind decoding without signaling from the network during initial access
Proposal 4: Support signaling via SIB1 the configurations for CORSET repetitions for CSS PDCCH other than Type 0 and Type 3:
Repetition number N
The time and frequency offsets of the subsequent N-1 CORSETs relative to the first CORSET.
FFS: The signaling details and PDCCHs to be supported.

Proposal 3: Support signaling of aggregation factors in SIB1 for PDSCH scheduled by a PDCCH in a CSS
Different aggregation factors are allowed for different PDSCH
FFS the list of PDSCH and the aggregation factors.

Proposal 4: For PDCCH in CSS other than Type 3 and Type 0, supports non-overlapping CORSET repetition of N times within a slot where the N repetitions of a PDCCH are transmitted in the N CORSETs using the same aggregation level and the same candidate index.
FFS: the value of N.

Proposal 5: Support slot aggregation for Msg4 PDSCH 
Different slot aggregation factors are allowed for different time windows defined by SFN
The configuration of Msg4 slot aggregation is signalled in SIB1.
FFS the list of PDSCH and the aggregation factors.


Proposal 6: For an NR NTN cell that supports SSB periodicity more than 20 ms for initial access, consider reducing the synchronization raster frequency points.


Proposal 7: For SSB periodicity greater than 20 ms, UE only monitors Type0-PDCCH within 40 ms of an SSB transmission. 


Proposal 8: The periodicity of SIB1 is 320 ms when SSB periodicity for initial access is more than 20 ms. 

3GPP TSG RAN WG1 #120bis		 R1-2502902
Wuhan, China, April 7th – 11th, 2025
Agenda Item:	9.11.1
Source:	Google
Title:	Discussion on Downlink Coverage Enhancement for NR NTN
Document for:	Discussion/Decision

Conclusion
Observation 1: Although RAN1 has agreed to support only the inter-slot repetition for Type0-CSS, we still see the benefits of intra-slot repetition in terms of a shorter satellite dwell time for cells with common message only.
Observation 2: Considering set 1-3 scenario, a legacy UE without the knowledge of Type0-CSS repetition has relative low probability to camp on the satellite due to insufficient link budget. In this regard, it is not mandatory to support legacy UE in this scenario.
Proposal 1: For Type0-CSS, support repeated PDCCH candidates in the two consecutive slots   and  associated with the same SSB index. (Option-1)
Base station applies parameter M=1 and M= ½ by selecting a SSB or SSB combination to be transmitted. (No spec impact)

____________________________________________________________________
3GPP TSG RAN WG1 #120bis			R1-2502920
Wuhan, China, April 7th – 11th, 2025	

Agenda item:	9.11.1
Source: 	CEWiT
Title: 	Discussion on Downlink Coverage Enhancements for NR NTN
Document for:	Discussion and Decision
____________________________________________________________________

Conclusion
This contribution includes the specification impacts on link and system level enhancements. 

Proposal 1: At least two repetitions can be considered to reduce the coverage gap for PDCCH at least for CSS.

Proposal 2: Intra slot repetition can be considered for PDCCH repetition for the minimum latency. 

Proposal 3:  Each repetition of Type0-PDCCH can have maximum number of PDCCH candidates per slot as it is inter slot repetitions

Proposal 4:  Each repetition of PDCCH, other than Type0-PDCCH, can have maximum number of PDCCH candidates per slot based on inter/intra  slot repetitions. 

Proposal 5: PDSCH timing can be decided based on the latest PDCCH repetition if the repetition is enabled. 

Proposal 6: For PDCCH repetition, apart from Type0, the same CORESET can be used with different search spaces.

Proposal 7: The searchspacelinkingID can be used to link two search spaces for the PDCCH candidates which carry the same DCI information in the consecutive slots for PDCCH repetition other than Type0-PDCCH. 


Proposal  8: Enable PDCCH repetition dynamically based on link quality.

Proposal 9: The reserved bit of the PBCH payload is preferred over the reserved bit of the MIB to indicate Type0-PDCCH repetition, as it minimizes latency.


Proposal 10: Support Cell DRX/DTX to turn ON/OFF the beams as a system level enhancement to improve the DL coverage for Rel-19 NR NTN. Rel-18 NES DRX/DTX mechanism should be modified for NTN specific scenarios as follows.
DTX/DRX can be beam-specific rather than cell-specific
SSB transmission should not be affected
Dynamic DTX/DRX patterns can be supported for a single beam as the satellite moves

Rel-19 NES introduces on-demand SSB/SIB1. Similarly, the UE can request the activation of a specific beam when it has traffic to transmit, and UE is in a RRC connected mode.

Proposal 11: Support on-demand beam activation when the UE has traffic to transmit to improve the DL coverage for Rel-19 NR NTN.

Proposal 12: Study the signalling of beam-specific DTX/DRX configurations via DCI, either by introducing a new DCI or modifying the existing DCI format.