3GPP TSG RAN WG1 #120-bis	R1-2501710
Wuhan, China, April 7th – 11th, 2025
Agenda Item:	9.6.1
Source:	Futurewei
Title:	Discussion on LP-WUS and LP-SS Design
Document for:	Discussion/Decision 

Conclusion
This contribution discusses the LP-WUS and LP-SS design options and considerations. The following summarizes our observations and proposals.
LP-WUS Structure
Observation 1: For LP-SS sync accuracy evaluation, the RAN1#118 agreed mandatory values for the 90% target timing estimation error represent the maximum tolerable time for the respective waveforms implying that an additional sync signal is required for LP-WUS if not received directly after the LP-SS.
Observation 2: For an LP-SS periodicity of 320 ms, OOK-1 may be supported without an additional sync signal preceding the LP-WUS assuming a 90% target residual time error of T≤2 μs and a residual frequency error <10 ppm. The 90% target residual time error may be relaxed as T≤3 μs if the residual frequency error is restricted to ≤5 ppm.
Observation 3: For an LP-SS periodicity of 320 ms, OOK-4/M=2 may be supported without an additional sync signal preceding the LP-WUS assuming a 90% target residual time error of T=0.5 μs but the residual frequency error is restricted to <5 ppm. The residual frequency error may be relaxed as <10 ppm if an LP-SS periodicity of 160 ms is supported.
Observation 4: OOK-4/M=4 may be supported without an additional sync signal preceding the LP-WUS assuming a 90% target residual time error of T=0.5 μs only if an LP-SS periodicity of 80 ms is considered and the residual frequency error is ≤5 ppm. 
Proposal 1: Support Option 1A (No additional sync signal with LP-SS periodicity ∈{80,160,320}ms) if the 90% target residual time error of T=0.5 μs is considered for OOK-4/M=2 and OOK-4/M=4 waveforms and the residual frequency error is restricted to ≤ 5 ppm for OOK-4/M=4 waveform. Otherwise, support Option 2.
Observation 5: Considering a 1% FAR target and a payload size (without Manchester encoding) of 12 bits, the number of 2 monitored codepoints per LP-WUS MO and/or up to 4 LP-WUS MOs per LO can be supported.
Proposal 2: Support LP-WUS to carry a code block length of at least 12 bits and up to 6 bits of message length with repetition after Manchester encoding for LP-WUS information carried by OOK.
Proposal 3: Support Alt 2, i.e., “Raw information bits are mapped to sequence(s) after channel coding”, with different rate matching and/or repetition factor as OOK for LP-WUS information carried by the overlaid OFDM sequence(s).

LP-WUS Waveform
Observation 6: OOK-4 waveform option with M=4 at 30kHz SCS can provide better spectral efficiency than other waveform options at least in RRC Connected state.
Proposal 4: Confirm the working assumption that a LP-WUR-enabled UE supports OOK-4 based LP-WUS design with M=4 regardless of SCS at least in RRC Connected state.
Proposal 5: Confirm the RAN1#118b working assumption that for OOK-1 and OOK-4 M=1, the overlaid sequence(s) are the sequence(s) of an OOK on symbol before DFT/LS processing.
Observation 7: The representative set of ZC roots q∈{1,13,18,21,26,27,35,52} has minimal impact (≤1dB) on the OFDM-based and ED-based LP-WURs performance without impairments at M=2 when the overlaid sequence carry 2 bits of information using four cyclic shifts .
Observation 8: Without impairments consideration, carrying 2 and 3 information bits by Nc=4 and Nc=8 candidate overlaid OFDM sequences can degrade the OFDM-based LP-WUR performance compared to carrying no information, i.e., Nc=1, by ~1.5 dB and ~4.5 dB, respectively.
Observation 9: Without impairments consideration and for the same target SNR as Nc=1 candidate overlaid OFDM sequence, different rate matching for OFDM-based LP-WUS than that considered for OOK-based LP-WUS, or two and three repetitions may be considered when Nc=4 and Nc=8 candidate overlaid OFDM sequences are used, respectively.
Observation 10: Without impairments consideration and for a target SNR of -0.5 dB, only for Nc=8 candidate overlaid OFDM sequences when considering the same coding and rate matching for OFDM-based LP-WUS as OOK-based LP-WUS, two repetitions may be required to achieve the target SNR. 
Observation 11: The combination of ZC sequence roots and cyclic shifts to carry LP-WUS information by the overlaid OFDM sequences has minimal impact on performance compared to the use of only cyclic shifts when impairments are not considered while it may provide better robustness against timing/frequency error impairments.
Proposal 6: For LP-WUS information carried by overlaid OFDM sequences, support the use of combination of ZC sequence roots and cyclic shifts at least for Nc=8 candidate overlaid OFDM sequences with at least two repetitions.
Observation 12: The use of OOK symbols and overlaid sequences for the detection of the LP-WUS source bits has minimal impact on the OFDM-based LP-WUR detection performance at least for Nc=8 candidate OFDM sequences, but can reduce the required detection time and subsequently improve power saving of the OFDM-based LP-WUR.
Proposal 7: Support the use of OOK symbols and overlaid sequences to detect the LP-WUS source bits for shorter OFDM based LP-WUR’s detection time and improved power saving.
Observation 13: Selection of the ZC root (or root pair) for the overlaid OFDM sequence(s) over OOK symbols based on the cell identifier can provide robustness against inter-cell interference for OFDM-based LP-WURs.
Proposal 8: Support UE’s determination of an overlaid OFDM sequence root/root pair based on cell identifier and cyclic shifts C_v according to C_v∈{l×⌊(M_q×B_ZC)/N_c⌋, l=0,1,…,N_c/M_q}, where M_q=1 for single roots and M_q=2 for root pairs. 
Observation 14: Selection of a cell-specific ZC sequence root/root pair for the overlaid OFDM sequence(s) over OOK symbols does not provide robustness against inter-cell interference for ED-based LP-WURs.
Observation 15: Selection of a cell-specific ZC sequence length B_ZC with ⌊L_ZC/B_ZC⌋ zero insertion between sequence samples for the overlaid OFDM sequence(s) over OOK symbols can provide robustness against inter-cell interference for ED-based LP-WURs.
Observation 16: ED-based LP-WURs can support LP-WUS detection at one of low-frequency envelope channels with low implementation complexity enabling robustness against narrowband and inter-cell interference handling.
Observation 17: Low frequency envelope channelization results in almost no performance degradation at ρ∈{-5,-10} dB and a performance degradation of only ~1 dB is noticed at ρ=0 dB.
Proposal 9: Support OOK-1 and OOK-4 based LP-WUS design with low frequency envelope channels to enable ED-based LP-WURs robustness against narrowband and inter-cell interference.

LP-SS Design
Observation 18: The performance of the LP-SS sequence sets for M=1 and L∈{4,6,8} does not meet the requirements to support the at least OOK-1 LP-WUS waveform without a LP-SS period <320ms or an additional synchronization signal.
Proposal 10: Do not support the LP-SS sequence sets for M=1 and L∈{4,6,8}.
Observation 19: Only the performance of the LP-SS sequence set for M=2 and L=16 can meet the requirements to support the OOK-1 LP-WUS waveform with a LP-SS period of 320ms and without an additional synchronization signal even at SNR = -6 dB. It can also meet the requirements to support the OOK-4 (M=2) LP-WUS waveform with a LP-SS period of 160ms at SNR = -3 dB.
Proposal 11: Do not support the LP-SS sequence sets for M=2 and L∈{8,12}.
Observation 20: The performance of the LP-SS sequence Set 2 for M=4 and L=16 can exceed the requirements to support the OOK-1 and OOK-4 (M=2) LP-WUS waveforms as that achieved by the LP-SS sequence set for M=2 and L=16 but at half the resource overhead and using only Y=1 LP-SS measurement sample to achieve the target RRM measurement accuracy instead of Y=4 samples.
Observation 21: The performance of the LP-SS sequence Set 2 for M=4 and L=32 can meet the requirements to support the OOK-4 (M=4) LP-WUS waveform with a LP-SS period of 80ms and without an additional synchronization signal at SNR = -3 dB.
Proposal 12: Do not support LP-SS sequence sets for M=2 & L=16, or LP-SS sequence Set 1 for M=4 & L∈{16, 32}. Only support LP-SS sequence Set 2 for M=4 and L∈{16, 32} to benefit from: 
lower resource overhead, 
lower number of required measurement samples, and 
improved timing synchronization performance.
Proposal 13: Support Alt2 for the M value, i.e., “the M values for LP-WUS and LP-SS can be configured to be same or different. M value for LP-WUS cannot be larger than that of LP-SS”.

RAN4#114 LS
Proposal 14: For RAN4 LS, the chip rate of LP-WUS or LP-SS OOK sequence can range from 14 kbps (OOK-1/M=1 at 15kHz SCS) to 112 kbps (OOK-4/M=4 at 30kHz) if the working assumption “M=4 for 30kHz SCS” is confirmed.
Proposal 15: For RAN4 LS, the length of information bits (the number of ON/OFF symbols for the single LP-WUS transmission) of OOK sequence can be ≥ 24 based on a 12 bit code block length and Manchester encoding.
Proposal 16: For RAN4 LS, the LP-WUS coding of information bits carried by OOK is based on Section 5.3.3.1, Section 5.3.3.2, and Section 5.3.3.3 for 1, 2, and >2 information bits, respectively, without CRC and with potential repetition before or after Manchester coding.

Conclusion 
In this contribution, the following proposals and observations have been made:
Proposal 1: Consider if pulse-shaping is required after sequence design and potential preamble are agreed.
Proposal 2: The DFT-shift is compensated at the LR.
Proposal 3: Do not consider mapping/quantizing WUS in frequency-domain.
Observation 1: Consider a channel encoding procedure for more than 11 information bits, e.g. 16 bits in RRC_CONNECTED mode.
Proposal 4: Specify Manchester Coding as 0 [1 0] and 1[0 1].
Observation 2: with Manchester Coding has the worst coverage compared to .
Proposal 5: For , consider jointly encoding multiple bits into ON pulse position to increase SNR by 3dB.
Observation 3: PAPR increase of Pulse Position Coding for  compared to Manchester encoding depends on the ratio of channel BW to WUS BW and is minor (~0.1dB) for many system configurations.
Proposal 6: Allow configuration of Pulse Position Coding for .
Proposal 7: Consider 4 different roots for inter-cell interference mitigation.
Proposal 8: CS(s) and/or roots(s) are derived from the WUS configuration without need for explicit signaling.
Proposal 9: Reuse ON-Sequences specified from sequences available if overlaid OFDM sequences carry information.
Observation 4: Correlation receiver achieves significant gain over energy detection.
Observation 5: For , Pulse Position Coding achieves significant performance gain for all receiver types.
Proposal 10: Support Alternative 1, mapping raw information bits to sequence(s)
Observation 6:
	COR-WUR performs better than COR-WUR-OOK due to the processing gain of carrying out longer correlations.
	Transmitting the same payload as the OOK waveform with the overlaid OFDM sequences but in a different bit sequence yields a significant performance gain.
	Using Pulse Position Coding and increasing the number of sequences results in a significant performance gain
Proposal 11: For multiple ON-Sequences, jointly encode the payload with OOK and sequence encoding.
Observation 7: A time-domain overlay code can significantly improve performance of the overlaid OFDM sequence transmission.
Observation 8: The receiver should be aware of which LP-SS sequence(s) to expect.
Proposal 12: Support of Pulse Position Coding for LP-SS for .
Observation 9: For  and , the detection performance of Set 2 is not optimal and can be improved.
Proposal 13: For  and , consider Set 3 for superior detection performance.

3GPP TSG RAN WG1 #120b  	          	              R1-2501767
Wuhan, China, April 7th–11th, 2025

Source: 	ZTE Corporation, Sanechips
Title:	Discussion on LP-WUS design
Agenda item: 	9.6.1
Document for:	Discussion and decision

Conclusions 
In this contribution, we have discussed issues on waveform design and signal structure for LP-WUS. We make the following observations and proposals:
Observation 1: For LP-SS, to configure equal number of OOK-ON symbols (carrying bit “1”) and OOK-OFF symbols (carrying bit “0”) within M OOK symbols for one OFDM symbol has benefits of 
Ensuring the power control implementation at gNB side unchanged;
Improving LP-RSRP/LP-RSRQ calculation accuracy; 
Ensuring the AGC performance;
Observation 2: For OOK-4 with M=1, only three of the agreed 4-length binary sequences can meet the requirement of TO correction accuracy <=5us.
Observation 3: For OOK-4 with M=1, the four agreed 6-length binary sequences can meet the requirement of TO correction accuracy <=5us.
Observation 4: For OOK-4 with M=1, the four agreed 8-length binary sequences can meet the requirement of TO correction accuracy <=5us.
Observation 5: For OOK-4 with M=1, compared with 6-length binary sequence, additional resource overhead of 33.3% for 8-length binary sequence can only bring additional TO estimation gain of 5.73%.
Observation 6: For OOK-4 with M=2, the four agreed 8-length binary sequences can meet the requirement of TO correction accuracy <=2us.
Observation 7: For OOK-4 with M=2, the four agreed 12-length binary sequences can meet the requirement of TO correction accuracy <=2us.
Observation 8: For OOK-4 with M=2,12-length binary sequences balances overhead and performance better compared to 8 binary sequences and 16 binary sequences, and has the same overhead as a 6-length sequence with M=1.
Observation 9: For OOK-4 with M=2, the four agreed 16-length binary sequences can meet the requirement of TO correction accuracy <=2us.
Observation 10: For OOK-4 with M=2, compared with 8-length binary sequence, additional resource overhead of 50% for 12-length binary sequence can bring additional TO estimation gain of 27.00%, additional resource overhead of 100% for 16-length binary sequence can bring additional TO estimation gain of 42.22% which is less than two times of 27.00%.
Observation 11: For OOK-4 with M=4, the four agreed 16-length binary sequences can meet the requirement of TO correction accuracy <=1us.
Observation 12: For OOK-4 with M=4, the four agreed 32-length binary sequences can meet the requirement of TO correction accuracy <=1us.
Observation 13: For OOK-4 with M=4, compared with 16-length binary sequence, additional resource overhead of 100% for 32-length binary sequence can bring additional TO estimation gain of 32.44%.
Observation 14: Without additional sync signal, based on residual frequency error 10ppm
if LP-SS periodicity is 320ms and M value >1, the LP-WUS shall use M=1 .
if LP-SS periodicity is 320ms and M value =1, the drifted TO is out of LP-WUS tolerance.
Observation 15: Without additional sync signal, based on residual frequency error 5 ppm
if LP-SS periodicity is 320ms and M value =1,2,4, the LP-WUS shall use M=1 to make sure the timer error in within 2us.
Observation 16: In low paging rate scenarios which is more practical for LP-WUS deployment, additionally sync signal can provide less overhead than smaller LP-SS periodicity.
Observation 17: Support additional sync signal has more flexibility for gNB and provide better sync performance for LP-WUS reception.
Observation 18: Option 2-2 can realize option 1A by configuration and provide more gNB flexibility, less overhead, and better sync performance for LP-WUS reception
Observation 19: If cases of 2 information bits and 1 information bit with independent channel coding solution are supported, the UE will attempt multiple channel decoding schemes when receiving LP-WUS, resulting in high complexity of LP-WUS detection.
Observation 20: Frequency offset caused by residual frequency error has impact on overlaid ZC sequence detection performance. 

Proposal 1: Confirm the working assumption in below agreement: 
Proposal 2: For the M value for LP-WUS and LP-SS, it should be configured by gNB respectively.
Proposal 3: Confirm the working assumption on overlaid OFDM sequence(s) of LP-WUS.
Proposal 4:Candidate LP-SS binary sequences should satisfy that
For OOK-4 with M>1, equal number of OOK-ON symbols (carrying bit “1”) and OOK-OFF symbols (carrying bit “0”) within M OOK symbols of one OFDM symbol for OOK-4 with M>1. 
For OOK-4 with M=1, equal number of OOK-ON symbols (carrying bit “1”) and OOK-OFF symbols (carrying bit “0”) within the binary sequence. 
Proposal 5: For OOK-4 with M=1, the following four 6-length binary sequences are supported for LP-SS.
[1 0 1 0 1 0]
[0 1 0 1 0 1]
[1 0 0 1 0 1]
[1 0 1 0 0 1]
Proposal 6: For OOK-4 with M=2, the following four 12-length binary sequences are supported for LP-SS.
[1 0 0 1 1 0 0 1 1 0 0 1]
[0 1 1 0 1 0 0 1 1 0 0 1]
[0 1 1 0 0 1 1 0 1 0 0 1]
[0 1 1 0 0 1 0 1 1 0 0 1]
Proposal 7: For OOK-4 with M=4, the following four 16-length binary sequences are supported for LP-SS.
[0 1 1 0 1 0 0 1 1 0 1 0 1 0 1 0]
[0 1 1 0 1 0 1 0 1 0 0 1 1 0 1 0]
[1 0 1 0 0 1 1 0 1 0 1 0 1 0 0 1]
[1 0 1 0 1 0 0 1 1 0 1 0 0 1 1 0]
Proposal 8: Option 1B can be precluded and down-select between option 1A and option 2.
Proposal 9: Support additional sync signal 
reuse LP-SS design
it is configurable
support larger and smaller LP-SS periodicity
Proposal 10: For LP-WUS information carried by OOK, channel coding schemes in section 5.3.3.2 of 38.212 for 2 information bits or 1 information is not supported.
Proposal 11: For LP-WUS information carried by OOK, RM coding as in section 5.3.3.3 of 38.212 with rate matching is supported before Manchester coding
Rate matching to a longer output binary sequence lager than 32 can be used as repetition.
Output sequence length after rate matching is preferred to integer multiples of 7 or 14.
Additional repetition after rate matching is not supported.
LP-WUS information bits size is no larger than 5 and detailed value can be configured through signaling.
Proposal 12: For LP-WUS information carried by the overlaid OFDM sequence(s), Alt2 is supported.
Rate matching after RM code is supported and the output sequence length should be an integer multiple of a bit size that can be carried by the ZC sequences in accordance with M value.
Proposal 13: For the overlaid ZC sequences, values of LZC and BZC for OOK-4 with M=1,2,4 are adopted as shown in the following Table.
Proposal 14: For LP-WUS overlaid ZC sequence generation, it is recommended to reuse NR preamble generation method of restricted type A.
ZC root index is prioritized to the root index with supporting larger number of ZC sequences with CS in the root index

3GPP TSG-RAN WG1 Meeting #120bis	                                                               R1-2501814
Wuhan, China, 07th – 11th April 2025

Source:	vivo
Title:	Discussion on LP-WUS and LP-SS design 
Agenda Item:	9.6.1
Document for:	Discussion and Decision

Conclusion
In this contribution, we provide our views on LP-WUS and LP-SS design aspects. The observations and proposals are summarized as follows.  
Observation 1: There is no need of specified DFT shift operation for LP-WUS/LP-SS signal generation.
Observation 2:  Option 1B is infeasible for M=4 case. 
Observation 3: For Option 1A,
160ms is feasible for M=1 case with LP-SS length 6& 8. 
320ms is feasible for M=2 case with all candidate LP-SS length (8, 12 and 16).
80ms is feasible for M=4 case with LP-SS length 32. 
Observation 4: Option 1A has smaller overhead than Option 2 for M=1, M=2, and when per UE paging rate =1% for M=4 (traffic set 1 in evaluation), while Option 1A has comparable overhead as option 2 when per UE paging rate =0.018% for IoT for M=4 (traffic set 2 in evaluation) case.  

Proposal 1: For RRC connected mode, LP-WUS is configured per BWP. The starting PRB of the LP-WUS is determined by offsetToCarrier corresponding to SCS of the active BWP and the configured offset with range of 0~ 264.
Proposal 2: For RRC idle/inactive state, LP-WUS/LP-SS frequency resource can be out of initial DL BWP. The LP-WUS/LP-SS starting PRB is determined by offsetToCarrier corresponding to SCS of the DL initial BWP and the configured offset with range of 0~ 264.
Proposal 3: For candidate M values, 
For FR1: Do not support M=4 OOK-4 for 30kHz SCS for RRC idle mode, FFS for RRC connected mode.  
For FR2: Support only M=1 for LP-WUS and LP-SS. 
Proposal 4: Support Alt 2 for LP-WUS/LP-SS M value, i.e., the M values for LP-WUS and LP-SS can be configured to be same or different. M value for LP-WUS cannot be larger than that of LP-SS. gNB separately configures M value for LP-WUS and LP-SS. 
Proposal 5: For RRC connected mode, gNB configures maximum number of codepoints which can be indicated by LP-WUS and  a list of codepionts to be checked by the UE. 
Maximum number of codepoints which can be indicated by  LP-WUS is in the range of 1 ~ 32. 
The number of elements in the codepoint list to be checked by the UE is up to 8, and the value of each element is in the range of 1~ maximum number of codepoints per LP-WUS. 
Proposal 6: For LP-WUS information carried by OOK, 
For larger than 2 information bits, RM coding with rate matching as section 5.4.3 in 38.212 is supported. 
For 2 information bits, coding as in section 5.3.3.2 of 38.212 with Qm =1 is applied. Rate matching as section 5.4.3 in 38.212 can be further applied.
For 1 information bits (if supported), coding as in section 5.3.3.1 of 38.212 with Qm =1 is applied. Rate matching as section 5.4.3 in 38.212 can be further applied. 
The code block length after rate matching can be from 1 to 32 bits. 
Note: no scrambling operation. 
Proposal 7: The overlaid OFDM sequence carries raw information bits (Alt 1) in order. 
Repetition can be applied to improve performance. Maximum repetition number, e.g., up to [4], can be provided by gNB. 
Proposal 8: For RRC connected mode, regarding the maximum number of candidates overlaid sequences to carry LP-WUS information per OOK ON chip for one cell:
support maximum 16 candidates overlaid sequences for M=1
support maximum 8 candidates overlaid sequences for M=2
Proposal 9: RAN1 clarifies the maximum number of overlaid OFDM sequences is 16/8/4 for M=1/2/4 for FR1, and 4/2/1 for M=1/2/4 for FR2, if corresponding M value for FR2 is supported. 
Proposal 10: For candidate root and cycic shift to support multiple overlaid OFDM sequences for LP-WUS in a cell, 
Support up to 2 roots 
Support up to 8/4/2 CS for M=1/2/4 for FR1, 2/1/1 CS for FR2 (if supported). 
Proposal 11: For LP-WUS overlaid OFDM sequence configuration in a cell, 
gNB configures number of sequences N1 (up to 16/8/4 for M=1/2/4), number of roots N2 (1 or 2) and a root index. 
The root can be any value between 1 ~ Bzc-1. 
In case of N2=2, second root value is (Bzc-q), where q is indicated for 1st root sequence.
The number of CS is derived by N1/N2. 
N1 sequences are enumerated in increasing order of first increasing cyclic shift of first root sequence, and then in increasing order of the root sequence index in case of N2=2.
Proposal 12: For LP-WUS transmission in a MO, 
MO duration is configured by gNB, in the range of one symbol to 5 or 6 slots. 
An MO is a valid MO, if the avaible symbols within the MO is no smaller than the configured LP-WUS length L, wherein the avaible symbols exclude TDD UL symbols, SSB and rate matching pattern provide by gNB. 
In the valid MO, LP-WUS maps to L OOK chips within avaible symbols.     
Proposal 13: For M=4 case, LP-SS binary sequence with  balanced ‘0’ and ‘1’ within one OFDM symbol is supported, i.e., set 1. 
Proposal 14: Support LP-SS binary sequences for M=1 & Length 8, M=2 & Length 16, and M=4 & Length 32. gNB configures the LP-SS binary sequence index for a cell.  
Proposal 15: For LP-SS with specified overlaid OFDM sequence, gNB configures a root value with default CS=0.
Proposal 16: RAN1 to discuss how to specify OOK generation, when LP-SS is not configured with specified overlaid OFDM sequence. 
Proposal 17: For LP-SS occasion, 
gNB configures a number of norminal occasions for LP-SS, wherein the number is no smaller than number of beams for LP-SS/LP-WUS. UE assumes LP-SS transmission with beam sweeping in valid occasions within the configured norminal LP-SS occasions, wherein  the valid occasion does not collide with UL symbols. 
gNB configures periodicty and slot-level offset for the first LP-SS occasion, e.g.,  
sl80, INTEGER {0..79}
sl160, INTEGER {0..159}
sl320, INTEGER {0..319}
sl640, INTEGER {0..639}
gNB configures symbol-level offset for the first LP-SS occasion, or the symbol-level offset is pre-defined. 
Remaining LP-SS occasions within a period is in consecutive slots with same symbol-level offset as the first LP-SS occasion. 
Proposal 18: Support option 1A with LP-SS periodicty of 80ms for at least M=4, 160ms for at least M=1, and 320ms or smaller periodicity for M=2, without addtional sync signal.

3GPP TSG RAN WG1 Meeting #120-bis											R1-2501845
Wuhan, China, April 7th –April 11th 2025

Agenda Item:	9.6.1
Source:	TCL  
Title:	LP-WUS and LP-SS Design
Document for:	Discussion and Decision 

Conclusion
In this contribution, we discussed the necessary information included in the LP-SS, LP-WUS for connected and idle/inactive UE, and made the following observations and proposals.
Observation 1: UEs in LP-WUS mode, using LP-SS for synchronization, must identify the transmitting cell, from which it receives the LP-SS, through its cell ID.
Proposal 1: RAN1 to consider including the physical cell ID (PCI) into the LP-SS signal
Proposal 2: For the candidate values of LP-SS periodicities, support 80ms, 160ms, 320ms, 640ms, 1280ms, and 2560ms for UEs in both RRC idle/inactive and connected states.
Proposal 3: Consider multiple candidate payload sizes for the LP-WUS, which can be configured to the UEs in both idle/inactive and connected states.
Proposal 4: For LP-WUS information carried by the overlaid OFDM sequence(s), support Alt 3: Codepoint/Subgroup is directly mapped to sequence(s).
Proposal 5: Support the following working assumption: 

Proposal 6: For the LP-WUS information used to trigger PDCCH monitoring for RRC connected UEs, to support the checking of up to 8 codepoints in a MO, the association/mapping between the codepoints in an LP-WUS and the MOs is configured to the UEs.

3GPP TSG RAN WG1 #120bis                                                      R1-2501875
Wuhan, China, April 07th – 11th, 2025

Agenda Item:	9.6.1
Source:	Spreadtrum, UNISOC
Title: 	Discussion on LP-WUS and LP-SS design
Document for:	Discussion and decision

Conclusion
We have the following proposals.
Proposal 1: The following working assumption should be confirmed.
Proposal 2: In RRC idle/inactive mode, the maximum information bit size per MO is 5.
Proposal 3: For connected mode, the maximum number of candidates overlaid sequences to carry LP-WUS information per OOK ON chip for one cell depends on UE capability.
Proposal 4: For WUS information carried by the overlaid OFDM sequence(s), raw information bits are mapped to sequence(s).
Proposal 5: If CRC length is small enough, OOK payload (channel coding + CRC) can be supported.
Proposal 6: OOK-1 can be supported for R19 LP-SS similar to LP-WUS.
Proposal 7: OOK-4 with M=2 or 4 can be supported for R19 LP-SS.
Proposal 8: LP-SS and LP-WUS has the same waveform in each combination.
Proposal 9: For LP-SS, multiple OFDM sequences overlaid on an OOK symbol may have low priority currently, but cell ID can be considered in OFDM sequence generation.
Proposal 10: LP-WUS/LP-SS frequency resource is configured within a carrier, which can be out of initial DL BWP.

3GPP TSG RAN WG1 #120bis                                                                                     R1- 2501999
Wuhan, China, April 7th – 11th, 2025
Source:            CATT
Title:                 Design of LP-WUS and LP-SS
Agenda Item:   9.6.1
Document for: Discussion and Decision

Conclusion 
In this contribution, we discuss the waveform design and sequence design of LP-WUS and LP-SS and give the following observations and proposals: 
Observation 1: For Case 1(with considering of preamble resource overhead within MO), it can be observed that:
The mean and minimum Hamming distance among the RM code block based on Method 1 and Method 2 are 0 for OOK-4 with M=4.
The mean and minimum Hamming distance of Method 3 is the maximum among the three patterns for M=2 and M=4.
Observation 2: For Case 2 (without considering of preamble resource overhead within MO), it can be observed that:
The minimum Hamming distance of Method 1 and Method 2 is 0 for OOK-4 with M=4 and M=2.
The mean and minimum Hamming distance of Method 3 is the largest among the three methods for M=2/4. 
The mean and minimum Hamming distance of three Methods are same for OOK-4 with M=1 and OOK-1.
Observation 3: The miss detection rate of the RM code block after coding based on Method 1 and Method 2 are always 1 for OOK-4 with M=4.
Observation 4: The 90% CDF of sync accuracy T can be achieved at 0.23us for M-sequence based LP-SS with M =1/2/4 with 15.36 MHz oversampling.
Observation 5: The 90% CDF of sync accuracy T can be achieved at 0.23us for M-sequence based LP-SS with 4~14 OFDM symbols duration of LP-SS with 15.36 MHz oversampling.
Observation 6: The 90% CDF of residual frequency error can be reduced at 30.3ppm for M-sequence based LP-SS with M=1, M=2 and M=4.
Observation 7: The maximum interval between LP-SS and LP-WUS is 165ms, 66ms and 33ms for M=1, M=2 and M=4, respectively.
Observation 8: The detection performance of LP-WUS would be degraded heavily caused by timing error while the periodicity of LP-SS is lager than165ms, 66ms and 33ms for M=1, M=2 and M=4, respectively.
Proposal 1: OOK-4 with M=1 is the DFT-S-OFDM waveform with low PAPR and should be supported.
Proposal 2: The OOK waveform of LP-WUS can be specified by a configurable variable M with value range {1, 2, 4}.
Proposal 3: The following two alternatives should be supported for RM code block generation for LP-WUS:
Alt 1: K bits information block [c1,…,ck] is encoded by subset matrix Gx,y (x=0,…,L-1; y=0,…,K-1) from the RM mother code matrix Mi,j (i=0,…,31; j=0,...,10) specified in TR 38.212 to generate L bits coded block [d1,…,dL] 
Gx,y = Mi_x, j_y, ((x=0~L-1, y=0~4) = (i_x =0~(L-1); j_y =1~5).
Alt 2: K bits information block [c1…ck] is encoded by RM mother matrix specified in TR 38.212 to generate 32 coded bits, di=( )mod2, i=0,…,31,j_k=1~5. The 32 bits coded block [d1…d32] is truncated to L bits code block [y1,…,yL] by puncturing (32-L) bits based on a puncture bit index set {L+1~32}.
Proposal 4: LP-WUS with the 1 or 2 information bit for wakeup indication should not be supported.
Proposal 5: The information bit size should be 5 to carry wake-up information.
Proposal 6: If preamble is not allocated within MO, the code block length can be 28bits, 14bits and 7bits for OOK-4 with M=4, OOK-4 with M=2 and OOK-4 with M=1/OOK-1, respectively.
Proposal 7: If preamble is allocated within MO, the code block length can be 20 bits, 10 bits and 5bits for OOK-4 with M=4, OOK-4 with M=2 and OOK-4 with M=1/OOK-1, respectively.
Proposal 8: The scrambling over the LP-WUS should not be supported.
Proposal 9: Repetition over RM coding before Manchester coding should not be supported.
Proposal 10: Block-level repetition after Manchester coding could be supported for coverage enhancement.
Proposal 11: It is needed to be clarified that the OFDM sequences are overlaid after Manchester coding at each ON chip.
Proposal 12: Support same maximum number of candidates overlaid sequences for both RRC_CONNECTED mod and RRC_IDLE/RRC_INACTIVE mods.
Proposal 13: The CS of overlaid OFDM sequence should be fixed according to the bandwidth index of LP-WUS.
Proposal 14: The set of root values for overlaid ZC sequence can reuse the principle of the root values specified for RACH Preamble in TS38.211 as shown in Table 6.
Table 9: The set of root value for different M

Proposal 15: The mapping between wakeup information and the root values should be discussed after the principle of the ZC root sequences selection are agreed.
Proposal 16: Support scheme 1: One overlaid OFDM sequence carries subset of subgroups specific indication or the common indication in one PO. 
Proposal 17: Alt 3 should be supported for low power consumption, better detection performance and low complexity.
Proposal 18: Alt 1: LP-WUS/LP-SS frequency resource is confined within initial DL BWP should be supported for RRC_IDLE/INACTIVE modes.
Proposal 19: Both OOK-1 and OOK -4 with M=1/2/4 can be supported for LP-SS waveform.
Proposal 20: Unified OOK waveform for LP-SS and LP-WUS can be supported.
Proposal 21: Support Alt1: The M values for LP-WUS and LP-SS are always same.
Proposal 22: The Manchester coding can be the supported for LP-SS as coverage enhancement same with LP-WUS.
Proposal 23: The following sequence sets of LP-SS should be supported:
For M=1, L=4, the set of LP-SS binary sequences is:
[0 1 0 1]
[0 1 1 0]
[1 0 0 1]
[1 0 1 0]
For M=2, L=8, the set of LP-SS sequence is:
[0 1 0 1 1 0 0 1]
[0 1 1 0 0 1 0 1]
[0 1 1 0 1 0 0 1]
[1 0 0 1 0 1 1 0]
For M=4, L=16, the set of LP-SS sequence is:
 [0 1 1 0 1 0 0 1 1 0 1 0 1 0 1 0]
[0 1 1 0 1 0 1 0 1 0 0 1 1 0 1 0]
[1 0 1 0 0 1 1 0 1 0 1 0 1 0 0 1]
[1 0 1 0 1 0 0 1 1 0 1 0 0 1 1 0]
Proposal 24: The unbalanced sequence set 2 for LP-SS should not be supported for M=4.
Proposal 25: The sequence length L=4/8/16 can be supported for M=1/2/4 , respectively.
Proposal 26: Support additional sync signal for LP-SS period longer than 165ms, 66ms and 33ms for M=1, M=2 and M=4, respectively.
Proposal 27: Alt 3: The resource of preamble is allocated outside of MO, each preamble resource associated with one or more MOs could be supported and can be specified by a configured offset between preamble resource and associated MO or an MO within a MO group.
Proposal 28: The sequence design for LP-SS can be reused for the Preamble.
Proposal 29: The M value of OOK-4 waveform or OOK-1 waveform for LP-SS, LP-WUS and Preamble should be configured to be the same in a cell to minimize the implementation complexity.

3GPP TSG RAN WG1 #120-bis	R1- 2502007
Wuhan, China, April 7th – April 11th, 2025
Agenda item:		9.6.1
Title:			LP-WUS and LP-SS design
Source: 			Nokia
Document for:		Discussion and Decision

Conclusion
In this document, we presented our initial thoughts on the WI scope and the topics that are relevant to be considered and discussed during the WI phase.
List of Proposals
Proposal 1:	The separation between LP-WUS/LP-SS and SSB in frequency domain must be restricted to ensure that all three physical channels experience similar fade.
Proposal 2:	As unified signal design is preferred to minimize the specification impact, pulse shaping for  shall not be considered, since in RAN1#119 it was agreed that  does not.
Proposal 3:	RAN1 should refrain from defining/using additional synchronization signal like preamble sequence before LP-WUS, since the codeword itself can be used as one.
Proposal 4:	To carry WUS information in overlay sequence, RAN1 shall consider Alt-2, which is same as the mapping used for underlying OOK transmission.
Proposal 5:	RAN1 should consider appending a known bits to the information bits (instead of CRC) to improve the detectability and coverage of LP-WUS.
Proposal 6:	RAN1 shall consider encoding of subgroup information using channel coding to extend the LP-WUS coverage.
Proposal 7:	As the expected traffic arrival rate is higher for connected mode, option 2C with known padded bits, is preferred for LP-WUS design.
Proposal 8:	We prefer Alt-2 as a suitable option for choosing  values between LP-SS and LP-WUS.
Proposal 9:	RAN1 shall consider the set of length 6 sequences for M=1, which provides sufficient accuracy for time and RSRP.
Proposal 10:	RAN1 shall consider length 12 sequences for M=2 to achieve desired level of estimation accuracy from both time and RSRP measurements.
Proposal 11:	RAN1 shall consider SET-1 with 16 length sequences for LP-SS using M=4.
Proposal 12:	We favour option 1B because there is no additional requirement to increase the periodicity of LP-SS to enhance either timing or RRM measurements.

List of Observations
Observation 1:	As SSBs are used for synchronization, RRM, entry, and exit conditions for LP-WUS monitoring, ensuring SSBs and LP-WUS/LP-SS to experience the channel state is necessary for reliability.
Observation 2:	Even after receiving the preamble before LP-WUS, the residual error cannot be zero as is the case with LP-SS. Therefore, LP-WUS detection still requires uncertainty window to perform detection.
Observation 3:	As codeword is used for LP-WUS mapping, LR can use two known sequences, namely, the specific subgroup sequence and all subgroup sequence, to perform search with uncertainty window determined by timing error, thus avoiding the need for preamble.
Observation 4:	Adding a preamble before LP-WUS increases the LR complexity by monitoring over additional window before the actual LP-WUS with very little benefit obtained from the timing accuracy.
Observation 5:	If the LR uses codeword as preamble and the desired sequence is not transmitted, the CRC check and the timing accuracy fails, without any impact on the performance. The timing correction should be performed only using LP-SS.
Observation 6:	During study item phase, few companies evaluated LP-WUS detection with an uncertainty window, which ensures detection reliability with time offset up to .
Observation 7:	The sequence overlaid in the ON duration of OOK signal must be robust against frequency offset as the accuracy of LO cannot be ensured for IQ receivers.
Observation 8:	Overlay sequence mapping based on segmentation of bits should consider encoded bit stream for bit segmentation and mapping, rather using the original information bits. By doing so, additional robustness can be obtained by employing block decoding.
Observation 9:	If  being the number of MOs, a LR must attempt at least  OOK ON symbols before determining the paging information with certainty for sub-group specific mapping.
Observation 10:	Both channel and receiver impairments degrade the cross-correlation properties and thus the performance of sub-group specific sequence mapping, i.e., option 2b.
Observation 11:	Unlike option 2b, option 2a is robust against receiver impairment to an extent due to fewer number of sequences. However, this increases the number of OOK symbols to be monitored.
Observation 12:	Depending on the encoding rate, LR may benefit from the soft/hard decoding of block encoded bits to improve the detection reliability.
Observation 13:	Overlay sequence with bit segmentation can provide better performance by adapting the number of bits mapped to a sequence as in constellation, thus providing a trade-off between the coverage and performance.
Observation 14:	Bit segment-based mapping with fixed number of sequences, i.e., Alt-2, provides better configurability to NW by varying the number of sequences.
Observation 15:	Using bitmap of paged UE information with encoding provides efficient approach to map the overlay sequence over ON symbols of LP-WUS that uses either bitmap or codepoint based scheme.
Observation 16:	If the codepoint scheme is used for overlay sequence, early terminal may not be possible by IQ receivers until all MOs are processed with respect to overlay sequence length.
Observation 17:	If overlay sequence mapping uses segmented bits to carry the intended sequence on each ON OOK symbol, restricting to only 1 or 2 sequences instead of all sequence correlation may not benefit is extracting the channel coding benefits.
Observation 18:	Adding CRC bits to the subgroup information increases the number of information bits, thus increasing the code rate and effectively reducing the detection performance.
Observation 19:	Adding a known bit instead of CRC before encoding improves the detection performance as it can be used as side-information at the detector employed at LR.
Observation 20:	Depending on the channel conditions, LR may resort to raw codeword detection or channel decoding of LP-WUS to determine the respective information.
Observation 21:	As the traffic arrival rate increases for UEs, only all-UE wake-up sequence is transmitted, and thus requiring only one MO.
Observation 22:	Averaging timing estimates obtained from multiple LP-SSs with predefined periodicity, the RTC can assumed to be calibrated to an accuracy of  with the help of NCO.
Observation 23:	LP-SS detection is performed as sequence correlation and not as symbol-by-symbol OOK detection for timing synchronization. Thus, it does not matter what  value used for LP-SS if LR uses a sequence stored as LUT and use it for correlation at a desired sampling rate.
Observation 24:	The choice of  used for connected mode should not be associated with the  value used for LP-SS as it is used only for idle operational mode.
Observation 25:	Using same  value for both LP-WUS and LP-SS may not be efficient as the requirement for timing offset itself will be the accuracy of estimation.
Observation 26:	In case of M=1, length 6 provides better compromise over timing and RSRP estimation accuracy while reducing the system footprint.
Observation 27:	Analyzing the sequences with M=2, length 12 provides a better compromise between timing and RSRP estimation accuracy without significant overhead.
Observation 28:	The sparse sequence proposed in SET2 is superior to SET1 from the timing estimation error only by a sample or two, which is insignificant while considering receiver imperfections.
Observation 29:	The timing estimation accuracy of SET1 vs SET2 sequences are comparable within a margin of 2 sample error between them, but due to similar power levels as LP-WUS, SET1 is preferrable.
Observation 30:	The detection accuracy can be improved by averaging the timing estimates over multiple LP-SS monitoring occasions, while ensuring the coherency of the channel fading.
Observation 31:	Using 320ms LP-SS periodicity together with the codeword detection of LP-WUS, we can avoid introducing additional overhead/signal design at the NW.

3GPP TSG RAN WG1 #120bis		R1-2502075
Wuhan, China, April 7th – 11th, 2025


Agenda item:	9.6.1
Source:	NEC
Title:              	Discussion on LP-WUS and LP-SS design
Document for:	Discussion and Decision

Conclusion
In this contribution, we discuss the LP-WUS and LP-SS design, and the following proposals are made:
Proposal 1: support flexibly configuring frequency locations of one or more LP-WUS bands within a carrier, UE can select an LP-WUS band based on its UE ID or a PF/PO it is intended to monitor.
Proposal 2: support message based LP-WUS structure with a preamble and a CRC.
Proposal 3: support repetition of LP-WUS to improve the coverage.
Observation 1: for UE with OFDM LR, it is beneficial if UE is allowed to receive only partial OOK symbols of LP-WUS and acquire the information bits based on the OOK on-off pattern and overlaid sequences of the partial OOK symbols.
Proposal 4: the order/pattern of information bits mapped to overlaid sequences should facilitate UE to acquire information bits based on partial OOK symbols, e.g., first half of the OOK symbols, of the LP-WUS.
Proposal 5: support FDM multiplexing of an LP-SS and its QCLed SSB.
Proposal 6: for each M values for LP-SS, support at least the following sequence length L:
M=1, L= 4
M=2, L= 8
M=4, L= 16

3GPP TSG RAN WG1 #120bis	R1-2502167
Wuhan, China, April 7th – 11th, 2025

Source: 	CMCC
Title:	Discussion on LP-WUS and LP-SS design
Agenda item:	9.6.1
Document for:	Discussion & Decision

Conclusions
In this contribution, we discussed the LP-WUS and LP-SS design, and the following proposals were made.
Proposal 1: For WUS information carried by the overlaid OFDM sequence(s), support Alt 1:
Alt 1: Raw information bits are mapped to sequence(s)
Proposal 2: The overlaid OFDM sequence carries WUS information bits in ascending order.
Proposal 3: Support to specify time domain signal before DFT/LS/IFFT processing for LP-WUS/LP-SS waveform generation for both OOK-4 and OOK-1.
Proposal 4: The multiplexing between legacy NR signal and LP-WUS/LP-SS should be before IFFT.
Proposal 5: Confirm the working assumption:
Regarding the LP-WUS information to trigger PDCCH monitoring of RRC connected UEs:
Codepoint based
The maximum number of codepoints checked per MO by a UE is up to 8
Depending on UE capability, a UE may support less than 8

Proposal 6: For LP-WUS information to trigger PDCCH monitoring of RRC connected UEs, both 1-to-1 and 1-to-all mapping from codepoint to UEs are supported.
Proposal 7: For the M value for LP-WUS and LP-SS, support Alt2: The M values for LP-WUS and LP-SS can be configured to be same or different. M value for LP-WUS cannot be larger than that of LP-SS.
Proposal 8: Support additional sync signal with LP-SS periodicity =320ms.
Without additionally support other LP-SS periodicities.
The LP-SS sequence can be reused as the additional sync signal.

3GPP TSG-RAN WG1 Meeting #120bis	R1-2502237
Wuhan, China, April 7th-11th, 2025

Agenda Item:	9.6.1
Source:	Huawei, HiSilicon
Title:	Signal Design of LP-WUS and LP-SS
Document for:	Discussion and Decision 

Conclusions
In this contribution, the design of LP-WUS and LP-SS are discussed. The following observations and proposals are made:

For WUS information carried by the overlaid OFDM sequence(s), Alt 2 have better detection performance than Alt 1, while the meaning of Alt 3 is not clear.
Obtaining different coded bits from overlaid OFDM sequences and from OOK ON/OFF pattern is beneficial.
A frequency offset of a ZC sequence will cause a shift of the correlation peak location of the ZC sequence in time domain, and the extent of this shift is determined by the value of root  and should be minimized by selection of root q.
With minimized range of the shift of correlation peak, optimized ZC root selection for LP-WUS allows UEs to have smaller sliding window and thus is beneficial to reduce UE implementation complexity.
Based on the property of ZC sequence
If timing error is smaller than half of the minimum cyclic shift, ZC sequences with the same root but different cyclic shift is the best choice because of smaller cross-correlation.
If timing error is larger than half of the minimum cyclic shift, ZC sequences with the different roots may be the best choice
Based on the property of ZC sequence
When different cyclic shifts of a ZC sequence with the same root are used as the candidate overlaid sequences, the timing error and frequency error need to be controlled within a target range when UE is detecting LP-WUS;
When ZC sequences with different roots are used as the candidate overlaid sequences, the timing error and frequency error can be relaxed when UE is detecting LP-WUS;
ZC sequences generated by the same root but difference cyclic shifts are not preferred to be used in different cells, since the timing difference between different cells may be larger than the minimum cyclic shift which results in strong interference.
If different roots for ZC sequences are used in different cells, no matter how large the timing difference of different cells is, the aperiodic cross-correlation is still good enough.
ZC sequences generated by the same root but different cyclic shifts are preferred to be used in the same cell to carry information for the following reasons, 
With the aid of LP-SS/SSB, the timing error and frequency error can be estimated and corrected to be smaller than a target range, thus LP-WUS can enjoy the benefit of lower cross correlation
Rate-matching is necessary for LP-WUS to adapt to different coverage performance requirement.
The rate-matching scheme defined in 38.212 is not optimized for 3~5 bits info length and <32 bits codeword length.
For codeword lengths between 16 and 32, rate-matching from the ‘tailing’ bits has larger minimum Hamming distance than that from the ‘heading’ bits.
Interleaving before rate-matching can provide nested length- 8, 16, 32 RM codes with larger minimum Hamming distance for rate-matched length shorter than 25.
To simplify the LP-WUS MO design, the candidate values of codeword length after rate-matching should limited.
With 1 or 2 information bits, the power saving gain of LP-WUS cannot be guaranteed.
With 1 or 2 information bits, the coverage performance cannot be efficiently improved.
For LP-SS, using different roots of ZC sequences on different OOK "on" symbols can improve receiving performance.
Low-density binary sequence to ensure one OOK ON symbol in each OFDM symbol for M=4 can also avoid transmit power wasting, but it impacts the frequency error estimation (for OFDM based receiver) , AGC and RRM measurements.
Scalable values of L for various M values are preferred, e.g., L={8, 16, 32} for M={1, 2, 4}.
MR can be used to calibrate the frequency of LP-WUR to control the initial frequency error. 
,If the periodicity of LP-SS is larger than 1280ms, the latency of obtaining RRM measurement results may be too large, which may restrict the UE max moving speed.
To support the functionality of falling back to MR and avoid too large latency of paging, the periodicity of LP-SS cannot be larger than 320ms.
The requirement of periodicity is usually dominated by the time error, where the residual frequency error contributes most of the time error.
To support the functionality of synchronization by periodic LP-SS only, the configured periodicity of LP-SS can be less or equal to 160ms.
Introducing preamble in addition to periodic LP-SS will increase the resource overhead.


For OOK-4, confirm the working assumption of M=4 is confirmed for 30kHz SCS.
For WUS information carried by the overlaid OFDM sequence(s), Alt 2 is supported, i.e., Raw information bits are mapped to sequence(s) after channel coding, where the same channel coding scheme(s) as OOK is applied.
Note: Rate-matching is still FFS
It is supported to let OFDM-based LP-WUR to get different coded bits from overlaid OFDM sequences and from OOK ON/OFF pattern by one of following option.
Option 1: The same coding and rate-matching order for OOK and overlaid OFDM sequences, and different mapping order from rate-matched bits to the OOK symbols/overlaid OFDM sequences.
Option 2: the same coding but different rate-matching order for OOK and overlaid OFDM sequences, then the same mapping order from rate-matched bits to the OOK symbols/overlaid OFDM sequences.
For the mapping from the coded bits to overlaid sequences, support a mapping order different from the mapping order of OOK sequences-based modulation, to enable OFDM-based receiver to terminate LP-WUS reception as early as possible.
The coded bits after rate matching are to be circularly repeated when the number of bits that can be carried by overlaid sequences are more than 32 bits or to be truncated to match the number of bits that can be carried by the OFDM symbols of a LP-WUS, which is similar as the operation in section 5.4.3 in TS 38.212. 
In order to reduce resource overhead, transmission duration of a LP-WUS targeting to wake up OFDM-based receiver can be shorter than the transmission duration required for ED based receiver.
In order to make ZC sequences robust to timing/frequency error, optimized roots of ZC sequences are selected.
Different overlaid ZC sequences can be used to minimize the interference between different cells.
Prefer to use different roots for different cells to minimize the interference.
Prefer to use different cyclic shifts to carry information.
For M=1, the frequency sequence after DFT is mapped to the center of 132 REs with 2 guard REs at each side.
Support enhanced rate-matching scheme after block codes defined in section 5.3.3.3 of 38.212, where the enhancement includes:
Rate-matching is performed by truncating from the heading bits or tailing bits based on the length of output codeword.
Before rate-matching, the codewords are interleaved   as 
The number of candidate codeword lengths is limited to (e.g. 4), where the candidate lengths can be selected based on minimum Hamming distances (e.g., {16, 12, 8, 4}).
For LP-WUS information carried by OOK, do not support cases with 1 or 2 information bits.
The design of LP-SS should follow the guidelines: 
Good auto-correlation and cross-correlation property taking into account modulation with CP 
Balanced '0's and '1's in the whole sequence
Balanced ‘0’ and ‘1’ within OFDM symbols for M>1.  
  For the M value relationship between LP-WUS and LP-SS, support Alt2, i.e., 
The M values for LP-WUS and LP-SS can be configured to be same or different. M value for LP-WUS cannot be larger than that of LP-SS.
If the LP-SS sequences need further down-selection, the choices are as follows:
M=1, L= 8
M=2, L= 16
M=4, L= 32 , Set 1
For both timing and frequency error evaluation purpose, the residual frequency error (Fr) can be <= 5ppm after assistance from MR.
For LP-SS periodicity, to support the functionality of RRM measurement by LP-WUR and the functionality of fallback operation, values larger than 320ms are NOT supported.
For LP-SS periodicity and preamble, support Option 1A, i.e., additionally support 160ms and does not support preamble.

3GPP TSG RAN WG1 #120bis		                                           R1-2502257
Wuhan, China, April 7th – 11th, 2025
Agenda Item:	9.6.1
Source: 	OPPO
Title:	Signal design for LP-WUS and LP-SS
Document for:	Discussion & Decision

Conclusion
In this contribution, we discussed the signal design for LP-WUS and LP-SS.  Observations and proposals are summarized as following.
LP-WUS
Support the same design of overlaid OFDM sequence length, i.e. LZC = 12*X/M for M=1. 
Confirm the working assumption for M=1 with removing the ‘DFT size is 2^n’. 
Confirm the working assumption. Support M=4 for 30KHz SCS. 
For LP-SS. 
Single overlaid sequence is on each OOK ‘ON’ symbol.
Prefer to use different roots, i.e. 4 roots to generate the overlaid OFDM sequence for different cells to minimize the interference. 
For case1 and case3, there is no relation for the overlaid OFDM sequence between LP-SS and LP-WUS. 
For case2, single overlaid OFDM sequence is on each OOK ‘ON’ symbol for LP-SS and LP-WUS, and the single sequence not carrying information. 
For case4, multiple candidates overlaid OFDM sequence could be used to carry information for LP-WUS. There is only one sequence is reused for LP-SS. 
In case of LP-SS reuse a specified overlaid OFDM sequence for LP-WUS, if same M value is configured for LP-SS and LP-WUS. It needs to determine which overlaid OFDM sequence is reused to generate the waveform of LP-SS. 
At least for case2, single overlaid OFDM sequence on each OOK ‘ON’ symbol not carrying information for LP-WUS and LP-SS, support to use the same overlaid OFDM sequence.
It needs to clarify which number of candidates overlaid sequences is supported except for the maximum value. 
Support same number of roots to generate the overlaid OFDM sequence for different M values. The number of roots is 4.
M=1,2: different roots with cyclic shift to generate the overlaid sequences
M=4: different roots to generate the overlaid sequences.
In case of one LO is associated with multiple POs, it needs to determine which PO’s subgroup is woke-up by the codepoint in LP-WUS.
In case of one LO is associated with multiple POs, multiple fields similar as PEI could not work directly.
In case of one LO is associated with multiple POs, support additional field to indicate the associated PO. The codepoint corresponding to the indicated PO is transmitted in another field.
Codepoint with 5bits payload is enough.
For connected mode, support multiple fields to indicate different codepoints in one LP-WUS.
The number of bits carried by the overlaid OFDM sequences is larger than or equal to the number of bits transmitted by OOK symbols.
Support alt2: Raw information bits are mapped to sequence(s) after channel coding.
If the number of bit sequence after rate matching is larger than the number of bit sequence before rate matching, i.e. E>N, the input bit sequence would naturally be repeated during transmission
No need to consider repetition before or after Manchester coding. Rate matching could have the same effect if gNB configure the enough resources.
Support rate matching after Manchester coding, regardless of whether channel coding or not before Manchester coding.

LP-SS signal
LP-SS uses a binary sequence associated to the cell ID by configuration. FFS: mapping schemes between cell ID and LP-SS sequences.
If support one LP-SS set for each M value. Considering same time duration of LP-SS with different M values. We suggest alt 1 or alt3.
Alt1: M=1, L=4; M=2, L=8, M=4, L=16;
Alt3: M=1, L=8; M=2, L=16, M=4, L=32;
If support only one LP-SS set. Considering the best sync performance. We suggest M=4, L=32.
Support sequence set2 for M=4.
For LP-WUS with M=1
Fe=5ppm:
If LP-SS could only be configured with same M value, i.e. M=1, LP-SS design should limit the Tr<5us, in this case, no need to support 80ms, 160ms periodicity for LP-WUS with M=1.
If LP-SS could be configured with larger M values, i.e. M=2, 4, maximum timing error of LP-SS is 3.6us<5us for 320ms periodicity. No need to support 80ms, 160ms periodicity for LP-WUS with M=1.
Fe=10ppm:
If LP-SS could only be configured with same M value, i.e. M=1, LP-SS design should limit the Tr<5us. In this case, when Tr=0.5,1us, no need to support 80ms, 160ms periodicity for LP-WUS with M=1. When Tr = 2us, at least need to consider 160ms periodicity for LP-SS.
If LP-SS could be configured with larger M values, i.e. M=2, 4, when Tr<2us, maximum timing error of LP-SS is 4.2us<5us for 320ms periodicity. No need to support 80ms, 160ms periodicity for LP-WUS with M=1.When Tr=2us, at least need to consider 160ms periodicity for LP-SS. 
For LP-WUS with M=2, when Fe=5ppm
If LP-SS could only be configured with same M value, i.e. M=2
When Tr = 2us, the timing error of LP-SS is 3.6us>3us for 320 ms periodicity. At least need to consider 160ms periodicity for LP-SS.
When Tr < 2us, i.e. Tr=0.5us,1us, the maximum timing error of LP-SS is 2.6us<3us for 320ms periodicity. No need to support 80ms, 160ms periodicity for LP-WUS with M=1.
If LP-SS could be configured with larger M value, i.e. M=4, maximum timing error of LP-SS is 2.6us<3us for 320ms periodicity. No need to support 80ms, 160ms periodicity for LP-WUS with M=2.
If LP-SS could be configured with smaller M value, i.e. M=1, 
When Tr = 0.5us,1us, the maximum timing error of LP-SS is 2.6us<3us for 320ms periodicity. No need to support 80ms, 160ms periodicity for LP-WUS with M=1.
When Tr = 2us, the timing error of LP-SS is 3.6us>3us for 320 ms periodicity. At least need to consider 160ms periodicity for LP-SS.
When Tr = 5us, LP-SS with 80ms periodicity still could not meet the performance requirement.

For LP-WUS with M=2, when Fe=10ppm
If LP-SS could only be configured with same M value, i.e. M=2, LP-SS with 320ms periodicity could not meet the performance requirement.
When Tr < 2us, i.e. Tr=0.5us,1us, at least need to consider 160ms periodicity for LP-SS.
When Tr = 2us, only LP-SS with 80ms periodicity could meet the performance requirement.
If LP-SS could be configured with larger M value, i.e. M=4, at least need to consider 160ms periodicity for LP-SS.
If LP-SS could be configured with smaller M value, i.e. M=1, 
When Tr = 0.5us,1us, at least need to consider 160ms periodicity for LP-SS.
When Tr = 2us, only LP-SS with 80ms periodicity could meet the performance requirement.
When Tr = 5us, LP-SS with 80ms periodicity still could not meet the performance requirement.

For LP-WUS with M=4,
when Fe=5ppm:
 Only LP-SS periodicity = 80ms under Tr=us could meet the performance requirement.
when Fe=10ppm:
All the LP-SS design could not meet the performance requirement.

Support Alt2: The M values for LP-WUS and LP-SS can be configured to be same or different. M value for LP-WUS cannot be larger than that of LP-SS.
Considering timing error requirement for M=4, support option 1A: No additional sync signal, LP-SS periodicity =320ms, and additional 80ms periodicity.
LP-WUS and LP-SS share the same frequency location, SSB location should be associated with LP-WUS/LP-SS.
Consider shorter periodicity like 80ms or 160ms for LP-SS.
Multiple LP-SSs can be transmitted in a period. Each LP-SS can be associated with a beam/SSB.
Support LP-WUS/LP-SS frequency resource can be out of initial DL BWP.

3GPP TSG RAN WG1 #120bis			R1-2502302
Wuhan, China, April 7th – 11th, 2025
                                      
Agenda Item:	9.6.1
Source:	InterDigital, Inc.
Title:	Discussion on LP-WUS and LP-SS design
Document for:	Discussion and Decision

Conclusion
In this contribution, we discussed LP-WUS and LP-SS design frameworks. From the discussions, we made following observations and proposals:
Observation 1. Considering shorter periodicities for the LP-SS or additional sync signal increases the synchronization overhead as well as receiver’s complexity.
Observation 2. In LP-SS based on OOK-4 with diverse values of M, the LP-WURs experience frequent need to change modulation order resulting in increased implementation complexity due to configured LP-SS having OOK-4 with different M values in serving and non-serving cells. 
Observation 3. In determining the binary sequences for LP-SS, considering more than one L-value per M-value could result in increased complexity, latency, and power consumption at UE-side.
Observation 4. In determining the binary sequences for LP-SS, the number of OFDM symbols could be different if the selected L-values for different M-values are not scaled with regards to each other.
Observation 5. Inaccuracy in RRM measurements based on LP-SS could cause inconsistency between RRM measurements based on LP-SS and NR-SS that could result in frequent false MR wake up.
Proposal 1. Support Option 1B with no additional sync signal, LP-SS periodicity = 320ms, and no additional support of other periodicities.
Proposal 2.  Confirm the working assumption on modulation orders for LP-SS to include both Option 1 with OOK-1 and Option 2 with OOK-4 and M = 2 or 4. 
Do not support additional M values.
Proposal 3.  Support Alt1 for M values selection, that is, the M values for LP-WUS and LP-SS are always same.
Proposal 4. In determining the binary sequences for LP-SS, support selecting one L-value applied to each M-value.
Proposal 5. In determining the binary sequences for LP-SS, support selecting the L-value applied to different M-values, such that the number of OFDM symbols is the same for different M-values.
Proposal 6. In determining the binary sequences for LP-SS, support following L-values:
For M = 1, support L = 8,
For M = 2, support L = 16,
For M = 4, support L = 32.
Proposal 7. Procedures for handling inconsistencies in RRM measurements based on LP-SS and RRM measurements based on NR-SS, e.g., due to RRM measurements inaccuracies based on LP-SS, should be supported.
Proposal 8. LP-WUS/LP-SS frequency resource can be configured out of initial DL BWP’.
Proposal 9: Support 5 bits as the maximum number of information bits.
Proposal 10: Down select raw information bits after channel coding (Alt 2) and codepoint/subgroup mapped to sequence(s) (Alt 3) are down selected for further down selection.
Proposal 11: The OOK waveform without overlaid OFDM sequence is not specified in RAN1 and define RAN4 requirements to guarantee the OOK detection performance.

3GPP TSG RAN WG1 #120-bis			                     R1-2502322
Wuhan, China,  07 – 11 April 2025
Agenda Item 	:	9.6.1
Source 	:	Sony 
Title 	:	LP-WUS and LP-SS design
Document for 	:	Discussion and decision

Conclusion
In this contribution, we have discussed our views on LP-WUS and LP-SS design and made the following observations and proposals.
Observation 1 – OOK-4 with M>1 has lower system overhead and can be detected with shorter delay using lower power LP-WUR, compared to OOK-1 or OOK-4 candidates with lower values of M. 
Observation 2 - The maximum number of bits per OFDM symbol, M, needs to be calculated based on LP-WUS bit rate, preventing ISI and the tolerable time/frequency errors by the LP-WUR. 
Observation 3 – Using the same SCS configuration as other NR has less complexity for gNB.

Observation 4 - To allow for fine synchronization and to prevent the NW from always-on transmission of LP-SS with short periodicity, it is beneficial that the LP-WUS also includes a preamble prior to its data information. 

Observation 5 – A use of a preamble before LP-WUS data part results in reduced power consumption at the UE while monitoring for LP-WUS. The LP-WUR first needs to only look for the preamble and it only continues to detect the data if the preamble is detected.

Proposal 1 – RAN1 to support setting M value to its maximum, i.e., M=4 for 30 kHz SCS and M=8 for 15 kHz to allow for low system overhead, lower latency and less power consumption at the LP-WUR.
Proposal 2 – RAN1 to support the same SCS configuration as other NR as it has less complexity for gNB.
Proposal 3 – Support LP-WUS structure with two fields, a preamble field for synchronization and cell identification purposes and a data field for indication of subsequent actions and/or wake-up group identity, depending on state of the operation.

Proposal 4 – RAN1 to support the use of one configured OFDM overlaid ZC sequence per UE and carry the LP-WUS data in a cyclic shift of the overlaid sequence.


Proposal 5 – RAN1 to support carrying information bits in cyclic shifts of the ZC sequence configured as  the OFDM LP-WUR synchronization sequence for the overlaid OFDM LP-WUS.

Proposal 6 – RAN1 to support that the OFDM sequence overlaid on the LP-SS is the same sequence used to carry data in its cyclic shifts on LP-WUS data symbols.

Proposal 7 – RAN1 to consider cell-ID, UE-ID and/or paging group-ID in the choice of the ZC sequence configured as for the overlaid OFDM LP-WUS.

Proposal 8 – When carrying information, the information carried in the overlaid sequence should be only for the purpose of reducing the total length of the LP-WUS received by OFDM based LP-WUR without degrading performance of the OOK-based LP-WUR. 

Proposal 9 – The OFDM overlaid sequence carrying cell information, should be only used for the purpose of assisting OFDM-based LP-WUR detection and not carrying any additional information that cannot be detected by the OOK-based LP-WUR.

Proposal 10 – RAN1 to consider having the same value of M for both LP-SS and LP-WUS.

Proposal 11 – Support inclusion of association of cell ID to the LP-SS sequences, e.g., by choosing LP-SS with max. value of M and L.
 
Proposal 12 – RAN1 to revise the agreed number of sequences and allow for larger number of sequences. 

Proposal 13 – Consider additional aperiodic synchronization signal where the signal/sequence is transmitted as part of LP-WUS. 

Proposal 14 - Support longer periodicity of LP-SS to allow reduced resource, power consumption and spectrum usage.

3GPP TSG RAN WG1 #120bis		R1-2502375
Wuhan, Hubei, China, April 7th – 11th, 2025
Agenda item:	9.6.1
Source:	Samsung
Title:	Discussion on LP-WUS and LP-SS design
Document for:	Discussion and Decision

Conclusion
The proposals and observation made in this contribution are summarized below:
Observation 1: To support large number of UEs per LP-WUS, the total number of required codepoints and the number of codepoints checked by a UE increase significantly especially when covering all possible wake-up indication cases by 1 LP-WUS transmission.
Observation 2: As the periodicity of LP-WUS MO decreases, the larger number of UEs can be associated per LP-WUS by using 1:1 and 1:2 mapping between codepoint and UEs, while restricting the number of UEs per LP-WUS should be necessary for longer MO periodicity.
Observation 3: If overlaid OFDM sequences over OOK symbol are specified, OOK-based LP-WUS can be detected either by envelope detection or correlation with OFDM sequence according to the type of LP-WUR.
Observation 4: If multiple candidates of OFDM sequences are specified to be overlaid by ON pulse of OOK symbol, it is beneficial for OFDM-based LP-WUR to reduce the power consumption of LP-WUS monitoring.

Proposal 1: Confirm the working assumption related to codepoint-based LP-WUS for RRC CONNECTED mode with the following modification:
Delete “Depending on UE capability, a UE may support less than 8.”
Add “Codepoint value set to be checked by a UE can be configured by the gNB.”
Proposal 2: For the maximum information bit size before coding, 5 or 6 bits can be considered as the candidates.
FFS: whether the same maximum information bit size is applied for different RRC mode, which maximum information bit size is used among 5 bits and 6bits.
Proposal 3: Regarding the coding scheme for OOK-based LP-WUS, support reusing the current specification as much as possible with the following details:
For 1 and 2bit information transmission, the section 5.3.3.1 and 5.3.3.2 in 38.212 can be applied respectively for code block generation using modulation order (Qm) equal to 1.
For more than 2bit information, the section 5.3.3.3 in 38.212 can be applied for length 32 code block generation.
After applying the coding, code block can be repeated or punctured based on rate matching.
No need to support scrambling and repetition on top of rate matching.
Proposal 4: Codepoint value without any coding schemes (including Manchester coding and rate matching) is carried by corresponding overlaid OFDM sequence via OOK ON symbol (i.e., Alt 1).
Unlike UE with OOK-based LP-WUR, UE with OFDM-based LP-WUR can meet the target FAR by setting the proper threshold for overlaid OFDM sequence detection.
FFS: repetition for the remaining ON symbols.
Proposal 5: For RRC CONNECTED, support UE capability reporting for the maximum number of candidates overlaid OFDM sequence per ON symbol.
Proposal 6: Regarding the determination on the number of cyclic shift values for overlaid OFDM sequences for RRC IDLE/INACTIVE, at least 4 different root values should be used to transmit information by the overlaid OFDM sequence (X=4).
Proposal 7: Root values of overlaid OFDM sequence per a cell can be configured by the gNB for both RRC IDLE/INACTIVE states.
The number of used cyclic shifts can be implicitly derived based on the number of overlaid OFDM sequence per ON symbol and the number of root values configured by the gNB, or explicitly configured by the gNB pairing with each root value.
Proposal 8: The gNB can configure the information bit size carried by overlaid OFDM sequences per ON symbol.
Explicitly or implicitly configure the monitoring window of OFDM-based LP-WUR within an LP-WUS monitoring occasion based on the number of overlaid OFDM sequence.
Proposal 9: For RRC idle/inactive, LP-WUS/LP-SS frequency resource is confined within initial DL BWP.
Proposal 10: Support configuring M values for LP-WUS and LP-SS to be same or different (Alt3).
Proposal 11: Further consideration on M values for 60kHz SCS and 120kHz SCS is necessary.
Consider limiting M value for 60kHz/120kHz to have the same maximum OOK chip rate with 15kHz/30kHz SCSs case (e.g., 112kcps).
Proposal 12: For the LP-SS binary sequence used in a cell, additional support of sequence determination by predefined rule is not needed.
Proposal 13. Regarding LP-SS binary sequence set for each M value, the sets with the following L value should be supported.
L=8 for M=1,
L=12 for M=2,
L=32 (set 2) for M=4.
Proposal 14: Support Option 1A with additional support for 160ms LP-SS periodicity.

TDoc file reading error

3GPP TSG RAN WG1 #120bis			                  R1-2502481
Wuhan, China, April 07th – 11th, 2025

Agenda Item:	9.6.1
Source: 	LG Electronics
Title: 	Discussion on LP-WUS and LP-SS design
Document for:	Discussion and decision

Conclusions
In this contribution, we have discussed on the various aspects for LP-WUS and LP-SS design, and the followings are proposed.
Proposal #1: Confirm to support OOK-4 with M=4 for 30 kHz SCS
Proposal #2: Not support M=4 for LP-WUS/LP-SS in FR2
Proposal #3: The maximum information bit size for both Idle/Inactive mode and Connected mode should be 5
Proposal #4: Support the following code block length for LP-WUS
For more than 2 information bits: gNB configures the code block length with maximum length of 32
For 2 information bits: code block length is 3 bits
For 1 information bit: code block length is 1 bit
Proposal #5: Not support adding scrambling bits for LP-WUS channel coding
Proposal #6: Additional repetition can be considered at least when the information bits carried by LP-WUS is 1 bit (FFS: for 2-bit information)
For more than 2 bits, no need to apply the additional repetition on top of RM coding
Proposal #7: For the overlaid OFDM sequence of OOK-4 with M=1, the sequence length  can be determined as , where  and  is the number of RBs of LP-WUS bandwidth (blanked guard RBs are not included)
Proposal #8: For the maximum number of candidates for the overlaid OFDM sequence per OOK ON symbol for a serving cell, consider the followings as a baseline capability for Connected mode UE
Maximum 16 candidates overlaid sequences for M=1
Maximum 8 candidates overlaid sequences for M=2
Maximum 4 candidates overlaid sequences for M=4
Proposal #9: For a given cell, different CS can be used to differentiate sequences
Different root for different cells to mitigate inter-cell interferences, if necessary
Proposal #10: Support the overlaid OFDM sequence carries the information bits without channel coding
FFS: Simple repetition can be further discussed
Proposal #11: Discuss the applicable M value for the small LP-WUS bandwidth
Proposal #12: For the overlaid OFDM sequence on each OOK ON symbol within an OFDM symbol, two sequences with different phases are alternatively used on each OOK ON symbol
Proposal #13: The bit ordering of information carried by overlaid OFDM sequence can be a shifted version of bit ordering for OOK symbols
Proposal #14: Discuss further the bit ordering of information carried by overlaid OFDM sequence when LP-WUS repetition is configured
Proposal #15: In case of overlaid OFDM sequence not carrying information, one sequence is selected from multiple candidates overlaid OFDM sequences which can be configured for the overlaid sequences carrying information bits
Proposal #16: Support the frequency resource for LP-WUS/LP-SS is confined within initial DL BWP
Proposal #17: Support the same frequency resource for LP-WUS and LP-SS
Proposal #18: Confirm the working assumption for LP-SS waveform generation
Proposal #19: At least for FR2, the value of M could be determined based on the SCS of LP-WUS/LP-SS
Proposal #20: The M value for LP-SS can be configured to be same or greater than that for LP-WUS
Observation #1: Applicable L for LP-SS can be configured depending on SCS for LP-WUS and SCS for LP-SS when multiple L values are configured to each M
Proposal #21: Discuss whether and how to configure the value of M for LP-SS with consideration of the followings:
Value of M for LP-WUS waveform
SCS of LP-WUS/LP-SS
LP-SS periodicity
Sequence length of LP-SS (i.e., LP-SS duration)
Proposal #22: Support multiple L values for each M considering flexibility for gNB perspective
L=4 and 8 for M=1
L=8 and 16 for M=2
L=16 and 32 for M=4
Proposal #23: Specify the overlaid OFDM sequence in frequency domain for OOK-1
Proposal #24: Overlaid OFDM sequence for LP-SS can be determined as one of the overlaid sequence candidates for LP-WUS
Proposal #25: Multiple LP-SS periodicities need to be supported for various scenarios
Proposal #26: Additional sync signal needs to be supported to accommodate M=4 for LP-WUS
Proposal #27: On the additional sync signal, Option 2 should be supported to receive LP-WUS which accommodates various M values
Option 2: With additional sync signal, LP-SS periodicity =320ms
Reuse the agreed binary sequence for additional synchronization signal

3GPP TSG RAN WG1 #120bis			R1-2502580
Wuhan, China, April 7th – 11th, 2025

Agenda Item:	9.6.1
Source:	Panasonic
Title:	Discussion on the LP-WUS and LP-SS design
Document for:	Discussion/Decision

Conclusion 
For RRC idle/inactive, LP-WUS is not supported for the case where associated CD-SSB and initial DL BWP have different SCSs


Agreement
At least for M>1, for the overlaid OFDM sequence length, support
Alt2:
Note: X is the number of RBs of LP-WUS/LP-SS bandwidth (blanked guard RBs are not included)



Agreement
Proposal 4.3-1: Update the agreements in RAN1 #118bis as below
Agreement
Support overlaid OFDM sequence(s) for LP-SS:
LP-SS reuses the overlaid OFDM sequence(s) specified for LP-WUS. The design on overlaid OFDM sequence(s) specified for LP-WUS doesn’t target for sync and RRM measurement performance based on overlaid OFDM sequence for LP-SS.
Applicable to both OOK-1 and OOK-4
Whether to transmit LP-SS by using a specified overlaid OFDM sequence is configurable.
Applicable at least for OOK-1 only and FFS for OOK-4
From RAN1 perspective, it is not intended to introduce new RAN4 requirements specific to overlaid sequences


Agreement
For RRC connected, for LP-WUS SCS:
Alt 1: LP-WUS SCS is same as the active DL BWP 


Working Assumption 
Regarding the LP-WUS information to trigger PDCCH monitoring of RRC connected UEs:
Codepoint based
The maximum number of codepoints checked per MO by a UE is up to 8
Depending on UE capability, a UE may support less than 8



Agreement
For M=2, 4, is given by the largest prime number such that,is the overlaid OFDM sequence length.
The base overlaid sequenceis generated by extension of
,
With CS(s) applied to the base overlaid OFDM sequence if any:denotes the potential cyclic shift (s)
,
Note it doesn’t preclude any pulse shaping scheme if any.



Agreement
For RRC connected, LP-WUS frequency resource can be outside of active DL BWP but has to be within the same carrier as the active DL BWP 
Basic capability is LP-WUS, if present, frequency resource within active DL BWP. LP-WUS frequency resource outside of active DL BWP is subject to separate UE capability
No RAN1 optimization specific to the case where LP-WUS frequency resource is outside of active DL BWP



Agreement
For M=1, L=4 (if supported), the set of LP-SS binary sequences is:
[0 1 0 1]
[0 1 1 0]
[1 0 0 1]
[1 0 1 0]

Agreement
For M=1, L=6 (if supported), the set of LP-SS sequence is:
[1 0 1 0 1 0]
[0 1 0 1 0 1]
[1 0 0 1 0 1]
[1 0 1 0 0 1]

Agreement
For M=1, L=8 (if supported), the set of LP-SS sequence is:
[1 0 1 0 0 1 0 1]
[1 0 1 0 1 0 0 1]
[1 0 0 1 0 1 0 1]
[0 1 0 1 0 1 0 1]

Agreement
For M=2, L=8 (if supported), the set of LP-SS sequence is:
[0 1 0 1 1 0 0 1]
[0 1 1 0 0 1 0 1]
[0 1 1 0 1 0 0 1]
[1 0 0 1 0 1 1 0]

Agreement
For M=2, L=12 (if supported), the set of LP-SS sequence is:
[1 0 0 1 1 0 0 1 1 0 0 1]
[0 1 1 0 1 0 0 1 1 0 0 1]
[0 1 1 0 0 1 1 0 1 0 0 1]
[0 1 1 0 0 1 0 1 1 0 0 1]

Agreement
For M=2, L=16 (if supported), the set of LP-SS sequence is:
[1 0 0 1 0 1 0 1 1 0 0 1 1 0 0 1]
[1 0 0 1 1 0 0 1 0 1 1 0 0 1 0 1]
[1 0 0 1 1 0 1 0 0 1 0 1 1 0 0 1]
[1 0 1 0 0 1 1 0 0 1 1 0 0 1 0 1]

Agreement
For M=4, L=16 (if supported), the set of LP-SS sequence is down-selected between:
Set 1
[0 1 1 0 1 0 0 1 1 0 1 0 1 0 1 0]
[0 1 1 0 1 0 1 0 1 0 0 1 1 0 1 0]
[1 0 1 0 0 1 1 0 1 0 1 0 1 0 0 1]
[1 0 1 0 1 0 0 1 1 0 1 0 0 1 1 0]
Set 2
[1 0 0 0 1 0 0 0 0 0 0 1 0 0 1 0]
[1 0 0 0 0 1 0 0 1 0 0 0 0 0 1 0]
[1 0 0 0 0 1 0 0 0 1 0 0 1 0 0 0]
[1 0 0 0 0 1 0 0 0 0 0 1 0 0 0 1]

Agreement
For M=4, L=32(if supported), the set of LP-SS sequence is down-selected between:
Set 1:
[0 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 1 0 1 0 0 1 1 0 0 1 1 0 0 1 0 1]
[0 1 1 0 0 1 0 1 0 1 1 0 0 1 0 1 1 0 0 1 1 0 1 0 1 0 1 0 0 1 0 1]
[0 1 0 1 0 1 0 1 1 0 1 0 1 0 0 1 1 0 1 0 1 0 0 1 1 0 1 0 0 1 1 0]
[0 1 0 1 0 1 1 0 0 1 0 1 1 0 1 0 0 1 1 0 0 1 1 0 1 0 1 0 0 1 0 1]
Set 2
[0 0 0 1 1 0 0 0 0 0 0 1 0 0 0 1 1 0 0 0 0 0 0 1 0 0 0 1 0 1 0 0]
[0 0 0 1 0 1 0 0 1 0 0 0 1 0 0 0 0 1 0 0 0 1 0 0 0 0 0 1 0 1 0 0]
[0 0 1 0 0 0 1 0 1 0 0 0 0 1 0 0 1 0 0 0 0 0 0 1 0 0 1 0 0 0 1 0]
[0 0 1 0 0 1 0 0 0 0 0 1 1 0 0 0 0 0 1 0 1 0 0 0 0 1 0 0 0 0 1 0]

Agreement
For idle mode, regarding the maximum number of candidates overlaid sequences to carry LP-WUS information per OOK ON chip for one cell:
support maximum 16 candidates overlaid sequences for M=1
support maximum 8 candidates overlaid sequences for M=2
For candidate overlaid sequences across all OOK ON chips of LP-WUS, the number of roots (in specification) is up to [FFS: X], FFS whether the number of roots can be different for different M value. 
FFS: The number of overlaid sequences applicable for a UE is no more than 2 per OOK ON chip.



Agreement
For WUS information carried by the overlaid OFDM sequence(s), consider at least the following alternatives:
Alt 1: Raw information bits are mapped to sequence(s)
Alt 2: Raw information bits are mapped to sequence(s) after channel coding
Same channel coding scheme(s) as OOK is applied.
FFS same or different rate matching and/or repetition factor as OOK
Alt 3: Codepoint/Subgroup is mapped to sequence(s)

3GPP TSG RAN WG1 #120bis	                                         	           R1-2502615
Wuhan, China, April 7th – 11th, 2025

Agenda Item:	9.6.1

Source:	Apple Inc.
Title:	LP-WUS and LP-SS design
Document for:	Discussion/Decision

Conclusion 
For RRC idle/inactive, LP-WUS is not supported for the case where associated CD-SSB and initial DL BWP have different SCSs

Agreement
At least for M>1, for the overlaid OFDM sequence length, support
Alt2:
Note: X is the number of RBs of LP-WUS/LP-SS bandwidth (blanked guard RBs are not included)

Agreement
Proposal 4.3-1: Update the agreements in RAN1 #118bis as below
Agreement
Support overlaid OFDM sequence(s) for LP-SS:
LP-SS reuses the overlaid OFDM sequence(s) specified for LP-WUS. The design on overlaid OFDM sequence(s) specified for LP-WUS doesn’t target for sync and RRM measurement performance based on overlaid OFDM sequence for LP-SS.
Applicable to both OOK-1 and OOK-4
Whether to transmit LP-SS by using a specified overlaid OFDM sequence is configurable.
Applicable at least for OOK-1 only and FFS for OOK-4
From RAN1 perspective, it is not intended to introduce new RAN4 requirements specific to overlaid sequences

Agreement
For RRC connected, for LP-WUS SCS:
Alt 1: LP-WUS SCS is same as the active DL BWP 

Working Assumption 
Regarding the LP-WUS information to trigger PDCCH monitoring of RRC connected UEs:
Codepoint based
The maximum number of codepoints checked per MO by a UE is up to 8
Depending on UE capability, a UE may support less than 8

Agreement
For M=2, 4, is given by the largest prime number such that,is the overlaid OFDM sequence length.
The base overlaid sequenceis generated by extension of
,
With CS(s) applied to the base overlaid OFDM sequence if any:denotes the potential cyclic shift (s)
,
Note it doesn’t preclude any pulse shaping scheme if any.

Agreement
For RRC connected, LP-WUS frequency resource can be outside of active DL BWP but has to be within the same carrier as the active DL BWP 
Basic capability is LP-WUS, if present, frequency resource within active DL BWP. LP-WUS frequency resource outside of active DL BWP is subject to separate UE capability
No RAN1 optimization specific to the case where LP-WUS frequency resource is outside of active DL BWP

Agreement
For M=1, L=4 (if supported), the set of LP-SS binary sequences is:
[0 1 0 1]
[0 1 1 0]
[1 0 0 1]
[1 0 1 0]

Agreement
For M=1, L=6 (if supported), the set of LP-SS sequence is:
[1 0 1 0 1 0]
[0 1 0 1 0 1]
[1 0 0 1 0 1]
[1 0 1 0 0 1]

Agreement
For M=1, L=8 (if supported), the set of LP-SS sequence is:
[1 0 1 0 0 1 0 1]
[1 0 1 0 1 0 0 1]
[1 0 0 1 0 1 0 1]
[0 1 0 1 0 1 0 1]

Agreement
For M=2, L=8 (if supported), the set of LP-SS sequence is:
[0 1 0 1 1 0 0 1]
[0 1 1 0 0 1 0 1]
[0 1 1 0 1 0 0 1]
[1 0 0 1 0 1 1 0]

Agreement
For M=2, L=12 (if supported), the set of LP-SS sequence is:
[1 0 0 1 1 0 0 1 1 0 0 1]
[0 1 1 0 1 0 0 1 1 0 0 1]
[0 1 1 0 0 1 1 0 1 0 0 1]
[0 1 1 0 0 1 0 1 1 0 0 1]

Agreement
For M=2, L=16 (if supported), the set of LP-SS sequence is:
[1 0 0 1 0 1 0 1 1 0 0 1 1 0 0 1]
[1 0 0 1 1 0 0 1 0 1 1 0 0 1 0 1]
[1 0 0 1 1 0 1 0 0 1 0 1 1 0 0 1]
[1 0 1 0 0 1 1 0 0 1 1 0 0 1 0 1]

Agreement
For M=4, L=16 (if supported), the set of LP-SS sequence is down-selected between:
Set 1
[0 1 1 0 1 0 0 1 1 0 1 0 1 0 1 0]
[0 1 1 0 1 0 1 0 1 0 0 1 1 0 1 0]
[1 0 1 0 0 1 1 0 1 0 1 0 1 0 0 1]
[1 0 1 0 1 0 0 1 1 0 1 0 0 1 1 0]
Set 2
[1 0 0 0 1 0 0 0 0 0 0 1 0 0 1 0]
[1 0 0 0 0 1 0 0 1 0 0 0 0 0 1 0]
[1 0 0 0 0 1 0 0 0 1 0 0 1 0 0 0]
[1 0 0 0 0 1 0 0 0 0 0 1 0 0 0 1]

Agreement
For M=4, L=32(if supported), the set of LP-SS sequence is down-selected between:
Set 1:
[0 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 1 0 1 0 0 1 1 0 0 1 1 0 0 1 0 1]
[0 1 1 0 0 1 0 1 0 1 1 0 0 1 0 1 1 0 0 1 1 0 1 0 1 0 1 0 0 1 0 1]
[0 1 0 1 0 1 0 1 1 0 1 0 1 0 0 1 1 0 1 0 1 0 0 1 1 0 1 0 0 1 1 0]
[0 1 0 1 0 1 1 0 0 1 0 1 1 0 1 0 0 1 1 0 0 1 1 0 1 0 1 0 0 1 0 1]
Set 2
[0 0 0 1 1 0 0 0 0 0 0 1 0 0 0 1 1 0 0 0 0 0 0 1 0 0 0 1 0 1 0 0]
[0 0 0 1 0 1 0 0 1 0 0 0 1 0 0 0 0 1 0 0 0 1 0 0 0 0 0 1 0 1 0 0]
[0 0 1 0 0 0 1 0 1 0 0 0 0 1 0 0 1 0 0 0 0 0 0 1 0 0 1 0 0 0 1 0]
[0 0 1 0 0 1 0 0 0 0 0 1 1 0 0 0 0 0 1 0 1 0 0 0 0 1 0 0 0 0 1 0]

Agreement
For idle mode, regarding the maximum number of candidates overlaid sequences to carry LP-WUS information per OOK ON chip for one cell:
support maximum 16 candidates overlaid sequences for M=1
support maximum 8 candidates overlaid sequences for M=2
For candidate overlaid sequences across all OOK ON chips of LP-WUS, the number of roots (in specification) is up to [FFS: X], FFS whether the number of roots can be different for different M value. 
FFS: The number of overlaid sequences applicable for a UE is no more than 2 per OOK ON chip.

Agreement
For WUS information carried by the overlaid OFDM sequence(s), consider at least the following alternatives:
Alt 1: Raw information bits are mapped to sequence(s)
Alt 2: Raw information bits are mapped to sequence(s) after channel coding
Same channel coding scheme(s) as OOK is applied.
FFS same or different rate matching and/or repetition factor as OOK
Alt 3: Codepoint/Subgroup is mapped to sequence(s)

3GPP TSG RAN WG1 #120bis	                          R1-2502675
Wuhan, China, April 7th – 11th, 2025

Source:	Sharp
Title:	         Discussion on LP-WUS and LP-SS design
Agenda Item:	9.6.1
Document for:	Discussion and decision

Conclusion
In this contribution, we have the following observations and proposals:
Proposal 1: No need to specify repetition after channel coding with rate matching for LP-WUS information. 
Proposal 2: Support CRC attachment after RM encoding.
Proposal 3: Consider the group size of different LP-WUS information within one LO in the LP-WUS design and apply different code rates accordingly.
Proposal 4：Support Lzc = 132 as the overlaid sequence length for M = 1.
Proposal 5: Support Option 1A, where no additional synchronization signal is required, and allow a smaller configurable periodicity for LP-SS.
Proposal 6: Consider two methods for configuring LP-WUS resources:
   - BWP-specific mode, where LP-WUS resources are configured per BWP.
   - Cell-specific mode, where LP-WUS resources are configured at the cell level.

3GPP TSG RAN WG1 #120bis	 R1-2502694
Wuhan, China, April 7th – 11th, 2025

Agenda Item:	9.6.1
Source:	HONOR
Title:	Discussion on LP-WUS and LP-SS design
Document for:	Discussion and Decision

Conclusions
In this contribution, we provide our views on waveform, detection scheme, and information carrying. The following observations and proposals are given:
Observation 1: When there are frequency domain errors, the performance of using only cyclic shift to generate the ZC sequence degrades significantly.

Proposal 1: Support alt3 for the M value for LP-WUS and LP-SS.
Proposal 2：Support M=4 for 30kHz SCS.
Proposal 3: The value of M is independent of SCS.
Proposal 4：Specify only the necessary steps for the design of OOK-1 and OOK-4.
Proposal 5: Specifies only the overlaid sequence for OOK-1.
Proposal 6: Specifies the two steps of sequence mapping and DFT for OOK-4.
Proposal 7: Further discuss how the UE obtains the OOK waveform generation scheme.
Proposal 8: The candidate overlaid sequence set of the cell is configurable.
Proposal 9: The overlaid sequence configuration reuses the configuration method of PRACH preamble sequences.
Proposal 10: Support alt3 in carrying information for overlaid sequences.
Proposal 11: Confirm the following working assumption:
Support the following options for LP-SS
Option 1: OOK-1 
Option 2: OOK-4 with M=2,4
The SCS of a CP-OFDM symbol used for LP-SS generation is the same as that used for LP-WUS generation
Proposal 12: The following options are supported for the length L of LP-SS binary sequence:
- M=1, L= {8}
- M=2, L= {16}
- M=4, L= {32}

3GPP TSG RAN WG1 Meeting #120-bis	R1-2502711
Wuhan, China, April 7th – 11th, 2025

Source:	MediaTek Inc.
Title:	LP-WUS and LP-SS design
Agenda item:	9.6.1
Document for:	Discussion and decision 

Summary
In this contribution, the following observations and proposals are provided:
Observation 1: Placing LP-WUS/LP-SS within the initial DL BWP and aligning them with the SSS enables immediate synchronization, eliminates additional retuning overhead, and allows the reuse of existing SSB-based frequency tracking, thereby simplifying UE wake-up detection and saving power.

Proposal 1: LP-WUS/LP-SS is located within the initial DL BWP and frequency-aligned with SSB.

Observation 2: Larger M value for LP-SS can provide better timing accuracy, while lower M value for LP-WUS can provide better timing error resistance.

Proposal 2: For the M value for LP-WUS and LP-SS, Alt 2 is selected, i.e., requiring M value for LP-WUS to be no larger than that of LP-SS.

Observation 3: RAN1 agreed support of 31 subgroups per PO, requiring minimum of 5 bits to be carried by LP-WUS. Extending the number of codepoints to 64 can further reduce FAR in connected mode where UE may possibly has more frequent wake-up because of frequent traffic types.

Proposal 3: Adopt a 6-bit information payload for LP-WUS (allowing 64 codepoints).

Observation 4: A single ZC root provides a streamlined approach for sequence generation and management, where cyclic shifts enable orthogonal or low-cross-correlation sequences with minimal complexity growth.

Proposal 4: Use a single ZC root sequence for LP-WUS overlaid sequences, with cyclic shifts mapping to the needed sequence variations for M = 1, 2, or 4.

Proposal 5: Specifically, 16 circular shifts of a ZC sequence of a given root are utilized, and j-th subset of circular shifts are utilized for the j-th possible on-chip occasion within a OFDM symbol, where j = 1, …, M and M = 1, 2, 4.

Observation 5: Minimizing reception time is crucial for OFDM-WUR, making coded bits (Alt 2) less desirable due to longer required reception time. Block-wise repetition in Alt 1 or Alt 3 offers flexible reception of fewer OFDM symbols in good SNR conditions, enhancing power efficiency.

Observation 6: Comparing Alt 1 and Alt 3, Alt 1 requires equal or less number of OFDM symbols to achieve 1% MDR and 1% FAR at both -0.5 dB and -3 dB SNR values.
Table 1: Number of required OFDM symbols for achieving 1% MDR and 1% FAR at -0.5 dB and -3 dB SNR values

Proposal 6: Adopt Alt 1 (Raw information bits are mapped to sequence(s)) for carrying information by the overlaid OFDM sequence(s). Note: Alt 1 embraces hierarchical subgroup mapping over multiple on-chips.

Observation 7: Carrying information via overlaid ZC sequence is sensitive to timing error. In particular, MDR exhibits error floor with residue timing error of 1 us for the case of M = 2 or 4. Having residue timing error close to 0.5 us is crucial for reliable LP-WUS detection.

Proposal 7: Adopt LP-SS with M = 4 and L = 32 to ensure LP-WUS performance for both OOK and OFDM WURs.

Observation 8: Unbalanced LP-SS achieves better absolute accuracy and less bias in the RSRP measurements.
Table 2: Measurement accuracy performance


Observation 9: Unbalanced LP-SS has PAPR of 6 dB, which is lower than PAPR of NR SSB (>9 dB).

Proposal 8: Support LP-SS design of M = 4, L = 32, and single on-chip within each OFDM symbol as this configuration provides the best synchronization and measurement performance.

Observation 10: With periodic LP-SS, LP-WUR can compensate sample clock error by offsetting the sample counting process. The residue timing error will be around 2x of accuracy error arisen from timing estimation over starting LP-SS and ending LP-SS of one period.

Proposal 9: With LP-SS sequences of good timing accuracy, Option 1B is adopted since LP-WUR can work with no additional synchronization and the baseline LP-SS periodicity of 320 ms.

3GPP TSG RAN WG1 #120bis			      R1-2502773
Wuhan, China, April 7th – 11th, 2025

Agenda item:	9.6.1
Source: 	NTT DOCOMO, INC.
Title: 	Discussion on LP-WUS and LP-SS design
Document for:	Discussion and Decision

Conclusion 
In this contribution, we discussed L1 structures on LP-WUS/LP-SS. Based on the discussion, we made following observations and proposals.
Observation 1
The LP-SS/LP-WUS resource overhead of total resource is 2.75%, which can be considered as marginal
Observation 2
Alt 1 can avoid the complexity of the network configuration
Observation 3
Early termination is important in terms of UE power saving
Observation 4
Repetition is important in terms of coverage improvements
Observation 5
If the information bit is fixed, the total bit length is known, so even if overlaid OFDM is repetitive, it can also be used for early termination
If the information bit is variable, by defining the number of repetitions, the UE can recognize the length of information bits and the number of repetitions and perform early termination
Observation 6
Based on Y=1 LP-SS sample, 
LP-SS with OOK-4 M=1, L=8 achieves T=2us accuracy with P=90% at SNR=-3dB
LP-SS with OOK-4 M=2, L=16 achieves T=2us accuracy with P=90% at SNR=-3dB
LP-SS with OOK-4 M=4, L=32 does not achieve T=1us accuracy with P=90% at SNR=-3dB 
Observation 7
Increasing the number of Y causes more overhead than increasing the number of L to achieve the same performance
Observation 8
LP-SS with OOK-4 M=4, L=32 almost achieves T=1us accuracy with P=90% at SNR=-3dB in case of Y=4
Observation 9
If LP-SS periodicity is larger than 1280ms, time drifting is larger than 1chip duration of OOK-4 M=4
Observation 10
For demodulation by the envelope detector, time error must be less than half the duration of one chip
If LP-SS periodicity is larger than 320ms, time error is larger than half of 1chip duration of OOK-4 M=4
Observation 11
The presence of a preamble results in a large overhead even if we assume single beam operation
The overhead needs to be minimized e.g., restrict preamble Tx occasion
The presence of LP-SS results in a large overhead when we assume multi beam operation
Observation 12
When there is no preamble for LP-WUS, it is necessary to limit the LP-SS periodicity
When there are preambles for LP-WUS, LP-SS periodicity limits can be relaxed
Observation 13
In case of 320ms LP-SS periodicity, BLER of OOK-4 M=4 has significant degradation, while not for M=1 and 2
For M=1 and 2,  preamble or LP-SS with shorter periodicity is not necessary
For M=4, either shorter LP-SS periodicity or introducing preamble is necessary. Comparing the LP-SS with shorter periodicity and preamble
From the perspective of overhead,  introducing preamble has less overhead
From workload perspective, the detail of preamble related issues has not been discussed yet and would take longer time for the specification
From the perspective of unified design, introducing preamble is not aligned with the principle better choice
Observation 14
Prefer Alt1: The M values for LP-WUS and LP-SS are always same
LP-WUS_Mvalue_IDLE/INACTIVE is enough for M value of LP-WUS and LP-SS configuration
Proposal 1
LP-WUS/LP-SS frequency resource is confined within legacy initial DL BWP
Proposal 2
The way of carrying the overlaid OFDM sequences is selected from the following options
Option 1: The information bits are arranged in order from front to back
Option 2: The information bits are set in order from the back
Proposal 3
The way of the overlaid OFDM sequences repetition is selected from the following options
Option 1: All information bits level repetition
Option 2: On chip bit group level repetition
Proposal 4
Overlaid OFDM sequence is used for both repetition and early termination
Proposal 5
For OOK-4 M=1, L=8 is supported 
For OOK-4 M=2, L=16 is supported 
For OOK-4 M=4, L=32 is supported
Proposal 6
Preamble is not supported
For OOK-4 M=4, Shorter LP-SS periodicity is supported e.g., 80ms, 160ms
Proposal 7
Remove the higher layer parameter [LP-SS_Mvalue] in higher layer parameters list
LP-WUS_Mvalue_IDLE/INACTIVE is used to configure the M values for both LP-WUS and LP-SS
Proposal 8
Regarding [LP-WUS/LP-SS_startRB_IDLE/INACTIVE] in higher layer parameters list,
Relative RB position from the edge or center of the initial DL BWP is configured
Proposal 9
Remove the bracket of [1…[4]]
Proposal 10
Regarding LP-SS_periodicityoffset in higher layer parameters list,
For M=1,2, UE assumes 320ms periodicity without higher layer configuration
For M=4, UE assumes [80 or 160]ms (to be down-selected) periodicity without higher layer configuration 
Proposal 11
Regarding [additionalsync] in higher layer parameters list,
Remove [additionalsync]
Proposal 12
Before discussing the details on LP-WUS_overlaidSeq_IDLE/INACTIVE and LP-WUS_overlaidSeq_CONNECTED  in higher layer parameters list, followings should be firstly discussed
How to send information via overlaid OFDM for LP-WUS in IDLE/INACTIVE mode and CONNECTED mode
Proposal 13
Regarding [Indicates the starting RB of LP-WUS in RRC CONNECTED] in higher layer parameters list,
Remove the bracket of [Indicates the starting RB of LP-WUS in RRC CONNECTED]
Proposal 14
Before discussing the details on WUS_codepoint_CONNECTED in higher layer parameters list, following should be firstly discussed
Whether a codepoint corresponds to [one or more] UEs

3GPP TSG-RAN WG1 Meeting #120bis	R1-2502805
Wuhan, China, April 7th – April 11th, 2025
Agenda Item:	9.6.1
Source:	Ericsson
Title:	LP-WUS and LP-SS design
Document for:	Discussion

Conclusion
In the previous sections we made the following observations: 
Observation 1	Compared to OOK-4 [M>1], OOK-1 [M=1] has lower complexity for both the UE and gNB and it can provide slightly better coverage. It is more robust against timing errors and requires a shorter LP-SS, leading to lower network energy consumption.
Observation 2	In the Idle/Inactive mode, OOK-4 [M>1] does not provide benefit over OOK1 while increasing both gNB and UE complexity and M=4 especially does not provide any benefit over M=2 while being more sensitive to timing error.
Observation 3	Even under ideal condition (without time/freq error) and single sequence detection, the OOK WUS duration of one slot is not sufficient to meet the -3dB SNR requirement.
Observation 4	For OOK based LP-WUS,
	For OOK-1 (M=1), 18-28 OFDM symbols are required to achieve 1%MDR for -3dB SNR depending on FAR assumption (0.1% vs 1%), and number of sequences checked by the UE.
	For OOK-4 (M=2,4) slightly more OFDM symbols than OOK-1 are needed to achieve same performance when same total power is assumed for the duration of LP-WUS transmission.
Observation 5	For mapping LP-WUS information to slots, some of the OFDM symbols in the slots must be reserved for other NR channels/signals and typically only a subset of OFDM symbols is available for LP-WUS mapping.
Observation 6	Regarding frequency position of LP-WUS/LP-SS:
	Alt 1 (LP-WUS/LP-SS frequency resource is confined within initial DL BWP) allows reusing existing BWP framework and procedures and reduces the need for UE RF returning and facilitates offloading of RRM measurements to WUR.
	The benefits of Alt2 (LP-WUS/LP-SS frequency resource can be out of initial DL BWP) over Alt 1 include more flexibility for placing WUS/LP-SS in the carrier, less congestion in the initial DL BWP, and potentially smaller overhead when supporting both RedCap and regular UEs.
Observation 7	Based on the current specifications, RedCap UEs should monitor paging in an initial DL BWP that contains CORESET#0 (i.e., UE may need to retune to regular initial DL BWP).
Observation 8	According to the current specifications (TS 38.211), there is no limitation on DFT size being a power of 2.
Observation 9	For OFDM detection, WUS duration of around 4 OFDM symbols is sufficient to reach -3 dB SNR.
Observation 10	For OFDM WUR, the frequency error can be up to a few kHz (e.g., 1-3 kHz) and the timing error is typically less than 0.2 us by relying on SSB.
Observation 11	For ZC sequence, different sequences can be created by combinations of different roots and cyclic shifts. For ZC sequence of length P (prime number), there are P-1 distinct sequences with different roots and multiple cyclic shifts for each root.
Observation 12	If the ZC sequences are generated with different roots and/or cyclic shifts (with sufficient separation), the cross correlations between them are low and do not increase the FAR.
Observation 13	To avoid any degradation on the sequence detection, the UE should only detect its intended sequences.
Observation 14	In the Idle mode the UE needs to detect up to 2 sequences: one its own sequence (or codepoint) and one common sequence (or codepoint).
Observation 15	Sequences with different roots are more robust against timing error/uncertainty compared to different cyclic shifts. Hence, multiple roots need to be considered for OFDM sequences.
Observation 16	The benefit of Alt 3 for carrying OFDM information is that the mapping of subgroup ID can be determined by an entire sequence over multiple OOK symbols and further optimization is possible by arranging the sequence candidates to reduce the cross-correlations/false alarms among the sequences.
Observation 17	The additional overhead and network energy consumption is significant for LP-SS periodicities 80ms or 160 ms.
Observation 18	To keep SNR degradation <1dB due to timing error (at 1%MDR)
	For OOK-1, timing error should be ≤ 6us
	For OOK-4, M=2, timing error should be ≤ 2us
	For OOK-4, M=4, timing error should be ≤ 1us
Observation 19	LP-SS duration of 4 or 6 OFDM symbols is suitable to provide sufficient timing accuracy for OOK1 and OOK4 (M=2). For M=4, the L-SS duration of 8 OFDM symbols is needed.
Observation 20	With LP-SS duration 4 or 6 OFDM symbols, the LP-SS beam sweeping can be done more efficiently compared to the 8-symbol LP-SS as two or three beams can perfectly fit within a slot with 12 available OFDM symbols.
Observation 21	For AWGN and TDL-C300_3 channel model with -3dB or -6dB SNR: 2-6 OFDM symbols of LP-SS transmission duration is needed to achieve comparable RSRP/RSRQ accuracy (less than ~3dB error) as 1 symbol SSS.
Observation 22	With 320 ms LP-SS periodicity, OOK-1 can properly work without the preamble given that it is relatively robust against the timing error. Hence, preamble is not necessary for OOK-1.
Observation 23	For OOK-4 (M=2, 4) and 320 ms LP-SS periodicity, the residual timing error can be reduced by preamble.
Observation 24	The overhead of preamble+LP-SS (320 ms periodicity) can be smaller than LP-SS-only (with < 320m periodicity).
Observation 25	Decreasing the LP-SS periodicity from 320 ms to 80 ms increases the overhead by 4x while by adding the preamble (with 320 ms LP-SS periodicity) the overhead increases by 1.02x-2.7x depending on the paging rate.  Moreover, decreasing LP-SS periodicity significantly increases the network energy consumption.
Observation 26	Considering both overhead and timing accuracy, using the preamble is preferred over more frequent LP-SS transmissions.
Based on the discussion in the previous sections we propose the following:
Proposal 1	Following principles should be considered for LP-WUS and LP-SS design
a.	It should be possible to generate LP-WUS/LP-SS transmissions using existing gNB hardware and not trigger any new emissions or compliance requirements.
b.	It should be possible to multiplex the LP-WUS/LP-SS with other NR transmissions in time or frequency domain without causing interference.
c.	It should be possible to reuse any unused LP-WUS time and frequency resources for other transmissions.
Proposal 2	Paging misdetection performance of the UE should not be impacted when LP-WUS is used by the UE for power savings.
Proposal 3	Regarding M value for LP-WUS and LP-SS, Alt 1 “the M values for LP-WUS and LP-SS are always same” is supported.
Proposal 4	LP-WUS should support any number of codepoints from 1 to 32 (targeting up to 31 subgroups and one common codepoint).
Proposal 5	Regarding LP-WUS information bits, all cases of 1 information bit, 2 information bits and larger than 2 information bits should be supported.
Proposal 6	The OFDM symbols used for LP-WUS should be indicated to the UE by configuring number of slots (A) used for LP-WUS (A=1,2 or [3] slots) an additional parameter indicating the available OFDM symbols in each slot (e.g., by configuring a 14-bit bitmap or by using a SLIV value).
Proposal 7	If repetition is supported for OOK-based LP-WUS, the OOK symbols after Manchester coding are repeated N_rep times. The N_rep repetitions occur in same MO.
Proposal 8	Maximum N_rep=[5] repetitions can be supported in the specifications considering different deployment scenarios, gNB flexibility to reserve some symbols in each slot for other transmissions, UE implementation margins etc., resulting in maximum MO duration for LP-WUS (i.e., after maximum repetitions) of [15] slots.
Proposal 9	The code-block length after channel encoding (i.e., N in 38.212 in section 5.3.3.3) is min (Y, (F*M)/2), where F is the number of WUS OFDM symbols with Manchester encoding, M is the number of OOK symbols per OFDM symbol, and Y=1, 3, and 32 for 1-bit, 2-bit, and ≥2 bits information, respectively. When (F*M)/2 > Y, the code-block is cyclically extended to fit the available OOK symbols.
Proposal 10	It should be possible to support or indicate 32 UE subgroup with one WUS, no segmentation.
Proposal 11	For regular UEs, the LP-WUS/LP-SS should be located within the initial DL BWP (as in Alt1). For RedCap, the LP-WUS/LP-SS can be located outside the separate RedCap initial DL BWP (as in Alt2) but within an initial DL BWP that includes CORESET#0 used for paging.
Proposal 12	In the working assumption from RAN1#118bis regarding OOK-1 and OOK-4 [M=1], the following note should be removed: “DFT size is 2^n”.
Proposal 13	LP-WUS design should allow OFDM-based LP-WUR to detect the information sent using OFDM sequences using a smaller monitoring duration compared to that of OOK-based LP-WUR (which detects information sent via OOK). i.e., low detection complexity and early termination should be ensured for OFDM WUR.
Proposal 14	The cyclic shifts of the OFDM sequences should be configured by the network.
Proposal 15	The number of roots for OFDM sequences (in the specification) for each M value should be at least 4.
Proposal 16	Optimal set of sequence roots can be determined based on a minimum cross-correlation metric. For four sequences roots, consider sets {2, 65, 68, 88}, {11, 35, 42, 44}, {5, 12, 23, 25} for M=1, 2, and 4, respectively.
Proposal 17	To carry OFDM information, further consider “Alt3: Codepoint/Subgroup is mapped to sequence” or “Alt1: Raw information bits are mapped to sequence(s)”.  “Alt 2: Raw information bits are mapped to sequence(s) after channel coding” should not be considered.
Proposal 18	Confirm the Working Assumption from RAN1#120 regarding codepoint scheme in connected mode.
Proposal 19	It should be possible for NW to flexibly configure the placement of LP-SS resources in frequency and time to minimize overhead and NW energy efficiency impact.
Proposal 20	LP-SS periodicities smaller than 320 ms should not be supported. Consider following values for configuring LP-SS periodicity: 320ms, 640ms, 1280ms, 2560ms.
Proposal 21	To ensure network flexibility for LP-SS transmissions and balance the tradeoff between overhead/network energy efficiency and timing accuracy in different SNR conditions, multiple LP-SS sequence lengths should be supported for each M value.
Proposal 22	LP-SS duration should be 4 or 6 OFDM symbols, corresponding to the following lengths for different M values: L= {4,6} for M=1, L= {8,12} for M=2, and L=32 for M=4.
Proposal 23	For LP-SS sequences of M=4, set 1 should be supported as it has lower PAPR while it provides similar performance as set 2.
Proposal 24	Including a preamble part before the data part of LP-WUS transmissions should be considered for OOK-based LP-WUS. The presence of preamble should be configurable.
Proposal 25	LP-SS periodicity smaller than 320 ms should not be supported.
Proposal 26	Regarding additional synchronization signal (i.e., preamble), among options identified in RAN1#119, Option 1B should be supported at least for OOK-1. For OOK-4 (M>1), Option 2 can be considered further.

​3GPP TSG RAN WG1 #120-bis			R1-2502846
Wuhan, China, April 7th – 11th, 2025
	
Agenda item:	9.6.1
Source: 	Qualcomm Incorporated
Title: 	LP-WUS and LP-SS Design
Document for:	Discussion and Decision

Conclusions
In this contribution, we have provided the following observations and proposals:
Observation 1: Using a single overlaid OFDM sequence without carrying information in the OOK On symbol helps extend the coverage of OOK LP-WUS.
Proposal 1: Clarify in the RAN1 #118bis agreement that in the case that overlaid OFDM sequence carries no information, the single overlaid sequence is configured by gNB as a known sequence to the UE.
Observation 2: A larger number of overlaid sequences requires higher memory usage over OOK ON chips.
Proposal 2: For each M=1, 2 or 4, the same set of candidate overlaid OFDM sequences is configured for all OOK ON chips for the LP-WUS.
Proposal 3: For idle/inactive mode, to keep the memory usage for storing overlaid sequences constant for different M values, the maximum number of roots configured in OOK On chips for M=1 and 2 is 1 and 2, respectively.
Proposal 4: For connected mode, the maximum number of sequences and roots over OOK On chips are UE capabilities.
Proposal 5: The maximum number of overlaid sequences applicable for a UE is 2 per OOK On chip if the common codepoint indicating all UE subgroups is configured in the LP-WUS MO. Otherwise, the maximum number of overlaid sequences applicable for a UE is 1 per OOK On chip.
Observation 3: For WUS information carried by the overlaid OFDM sequence(s), Alt. 1 allows for repetitions of WUS information in the LP-WUS MO and early termination of WUS information detection by UEs in good channel conditions.
Observation 4: For WUS information carried by the overlaid OFDM sequence(s), the benefits of robust and early detection of Alt 2 is not essential in comparison to Alt 1.
Proposal 6: Support Alt 1: Raw information bits are mapped to sequence(s) for WUS information carried by the overlaid OFDM sequence(s).
Observation 5: To achieve an overall maximum 1% FAR for LP-WUS detection, the maximum probability that one codepoint is falsely detected as another codepoint should also be 1%. 
Observation 6: When the minimum Hamming distance is above half the sequence length, the overall FAR for correlation based OOK LP-WUS detection is dominated by the inter-code false detection errors.
Proposal 7: For OOK LP-WUS design, the minimum Hamming distance should be not smaller than half the sequence length.
Observation 7: 16 OFDM symbols are needed to achieve the 1% MDR and 1% FAR at SNR = -3dB.
Observation 8: NR rate matching introduces severe Hamming distance loss for RM code based OOK LP-WUS sequence design
Even for sequence length = 8 and 16, the number of information bits carried by the sequence generated by RM codes (5.3.3.3 of TS 38.212) and rate matching (5.4.3 of TS 38.212) is smaller than length 8 and 16 Hadamard sequences when the minimum Hamming distance is >= half the sequence length.
Proposal 8: To generate the OOK LP-WUS from RM code, replace the NR rate matching by Table 2. The sequence generation procedure includes the following steps:
For a sequence length  (), determine the maximum number of information bits  that satisfies the minimum Hamming distance requirement  according to [5]
Add a zero prior to the first bit of the input information bit vector i.e., convert  to 
Encode the bits according to section 5.3.3.3 from TS 38.212
Select the encoded bits from the 32-bit output according to Table 2 in section 2.2.3.1 where each row contains positions of bits retained from the 32-bit RM encoded bits.
Proposal 9: Sequences for OOK LP-WUS can be generated by NR RM code in the following steps
Choose the number of information bits  depending on the desired sequence length  according to Table 1 in section 2.2.3
Define the following bit selection vectors. The th value in the vector is associated with the th row of the corresponding  matrix defined in section 2.2.3.2 and it is the row index for a row of the matrix spanned by Mi,1 to Mi,K in Table 5.3.3.3-1 that contains the same binary combination as the th row of the  matrix
 = [0 3 1]
 = [0 2 6 4 3 8 1]
 = [5 14 13 16 24 10 0 3 7 1 8 4 2 6 9]
 = [13 2 16 3 14 15 6 4 9 0 8 10 1 7 24]
 = [15 30 14 12 10 6 24 16 21 26 9 19 11 0 5 18 7 27 29 20 2 13 1 4 22 8 23 25 28 3 17]
If  is not a power of 2, add a zero prior to  of the input (from  to ) and select the vector 
If  is a power of 2, select vector , and append 31 at its end
Encode the bits according to section 5.3.3.3 from TS 38.212
Select and reorder bits according to the indices contained in selected  vector
E.g., if  is the output of the RM encoding process and we selected , then the output of this step is 
If necessary (), apply rate matching as described in section 5.4.3 from TS 38.212
Observation 9: For the short MO LP-WUS with a single LP-WUS configured per MO, LP-WUS with a duration of minimum 2 OFDM symbols can meet the performance requirements at SNR=-3dB.
Proposal 10: Support LP-WUS with short duration, with the number of codepoints per MO equal to 1. Network can configure one of the following two modes
Mode 1 with one sequence: a sequence is transmitted in the MO to indicate the associated UE to monitor PDCCH, no signal is transmitted in the MO if the associated UE does not to monitor PDCCH
Mode 2 with two sequences: a first sequence is transmitted in the MO to indicate the associated UE to monitor PDCCH, a second sequence (! first sequence) is transmitted in the MO to indicate the associated UE to not monitor PDCCH
Observation 10: Preamble helps reduce periodicity of periodic LP-SS transmission and reduce system overhead. 
Proposal 11: Support preamble in the LP-WUS.
Observation 11: Configuring the same M value for LP-WUS and LP-SS makes it easier for LP-WUR implementation.
Proposal 12: Support the M values for LP-WUS and LP-SS are always same.
Observation 12: For LP-SS binary sequences selected in RAN1 #120, there is sequence detection ambiguity for random timing error up to ±25 µs
For M=1 and L=4, UE cannot distinguish “0101” and “1010” 
For M=1 and L=6, UE cannot distinguish “010101” and “101010”
Proposal 13: Do not specify LP-SS binary sequences for {M=1, L=4} and {M=1, L=6}.
Proposal 14: For RRC idle/inactive, support Alt 1: LP-WUS/LP-SS frequency resource is confined within initial DL BWP.

3GPP TSG RAN WG1 #120b	R1-2502880
Wuhan, China, Apr 7th - Apr 12th, 2025

Agenda item:		9.6.1
Source:	Nordic Semiconductor ASA
Title:					On LP-WUS and LP-SS design
Document for:		Discussion and Decision

Conclusions 
Proposal-1: Set of root sequence indices and corresponding cyclic-shifts are configured to a UE according to table below. .

Proposal-2: Manchester coding is applied to every LP-WUS by default, i.e. irrespective of M and SCS. 

Proposal-3: To simplify LP-WUS design, support only payloads of 3 and 5bits for LP-WUS
take 32bit codeblock length as baseline.
consider the same LP-WUS length for 3 and 5 bit payloads.
for repetitions consider sequential reading from circular buffer.

Proposal-4: For information mapping to overlaid sequences, in RAN1#120b collect proposed mapping schemes from contributions and discuss KPIs.

Proposal-5: Length of binary sequence is , i.e. there are three different sequence length, one for each M.

Proposal-6: Our preference is Option 1A
	Option 1A: No additional sync signal, LP-SS periodicity =320ms
Additionally support at least one of [80ms,160ms] for M=4

3GPP TSG-RAN WG1 Meeting #120-bis	        R1-2502908
Wuhan, China, April 7th – 11th, 2025

Agenda Item:	9.6.1
Source:	Lenovo
Title:	Discussion on LP-WUS and LP-SS design
Document for:	Discussion

Conclusions
In this contribution, considerations of LP-WUS and LP-SS designs are provided. The following proposals are present: 
Observation 1: LO closer to the LP-SS does not need any preamble however the drift happens when the LO is configured away from LP-SS

Proposal 1: Consider preamble transmission before LO when the offset between LP-SS and the starting of LO can be more than configured value. 

Proposal 2: UE can benefit from power consumption, when the preamble can be configured closer to the monitoring occasion containing codepoint corresponding to all subgroups in a LO  

3GPP TSG RAN WG1 #120-bis	R1- 2503000
Wuhan, China, April 7th – April 11th, 2025
Agenda item:		9.6.1
Title:			LP-WUS and LP-SS design
Source: 			Nokia
Document for:		Discussion and Decision

Conclusion
In this document, we presented our initial thoughts on the WI scope and the topics that are relevant to be considered and discussed during the WI phase.
List of Proposals
Proposal 1:	The separation between LP-WUS/LP-SS and SSB in frequency domain must be restricted to ensure that all three physical channels experience similar fade.
Proposal 2:	As unified signal design is preferred to minimize the specification impact, pulse shaping for  shall not be considered, since in RAN1#119 it was agreed that  does not.
Proposal 3:	RAN1 should refrain from defining/using additional synchronization signal like preamble sequence before LP-WUS, since the codeword itself can be used as one.
Proposal 4:	To carry WUS information in overlay sequence, RAN1 shall consider Alt-2, which is same as the mapping used for underlying OOK transmission.
Proposal 5:	RAN1 should consider appending a known bits to the information bits (instead of CRC) to improve the detectability and coverage of LP-WUS.
Proposal 6:	RAN1 shall consider encoding of subgroup information using channel coding to extend the LP-WUS coverage.
Proposal 7:	As the expected traffic arrival rate is higher for connected mode, option 2C with known padded bits, is preferred for LP-WUS design.
Proposal 8:	We prefer Alt-2 as a suitable option for choosing  values between LP-SS and LP-WUS.
Proposal 9:	RAN1 shall consider the set of length 6 sequences for M=1, which provides sufficient accuracy for time and RSRP.
Proposal 10:	RAN1 shall consider length 12 sequences for M=2 to achieve desired level of estimation accuracy from both time and RSRP measurements.
Proposal 11:	RAN1 shall consider SET-1 with 16 length sequences for LP-SS using M=4.
Proposal 12:	We favour option 1B because there is no additional requirement to increase the periodicity of LP-SS to enhance either timing or RRM measurements.
Proposal 13:	RAN1 shall reuse the existing RM encoding and rate matching as in section 5.3.3.3 of 38.212 with either repeating the information bits or appending known bits before encoding.
Proposal 14:	RAN1 shall deprioritize additional synchronization signal and instead account the decoding to improve detection reliability and coverage.

List of Observations
Observation 1:	As SSBs are used for synchronization, RRM, entry, and exit conditions for LP-WUS monitoring, ensuring SSBs and LP-WUS/LP-SS to experience the channel state is necessary for reliability.bservation 2:	Even after receiving the preamble before LP-WUS, the residual error cannot be zero as is the case with LP-SS. Therefore, LP-WUS detection still requires uncertainty window to perform detection.
Observation 3:	As codeword is used for LP-WUS mapping, LR can use two known sequences, namely, the specific subgroup sequence and all subgroup sequence, to perform search with uncertainty window determined by timing error, thus avoiding the need for preamble.
Observation 4:	Adding a preamble before LP-WUS increases the LR complexity by monitoring over additional window before the actual LP-WUS with very little benefit obtained from the timing accuracy.
Observation 5:	If the LR uses codeword as preamble and the desired sequence is not transmitted, the CRC check and the timing accuracy fails, without any impact on the performance. The timing correction should be performed only using LP-SS.
Observation 6:	During study item phase, few companies evaluated LP-WUS detection with an uncertainty window, which ensures detection reliability with time offset up to .
Observation 7:	The sequence overlaid in the ON duration of OOK signal must be robust against frequency offset as the accuracy of LO cannot be ensured for IQ receivers.
Observation 8:	Overlay sequence mapping based on segmentation of bits should consider encoded bit stream for bit segmentation and mapping, rather using the original information bits. By doing so, additional robustness can be obtained by employing block decoding.
Observation 9:	If  being the number of MOs, a LR must attempt at least  OOK ON symbols before determining the paging information with certainty for sub-group specific mapping.
Observation 10:	Both channel and receiver impairments degrade the cross-correlation properties and thus the performance of sub-group specific sequence mapping, i.e., option 2b.
Observation 11:	Unlike option 2b, option 2a is robust against receiver impairment to an extent due to fewer number of sequences. However, this increases the number of OOK symbols to be monitored.
Observation 12:	Depending on the encoding rate, LR may benefit from the soft/hard decoding of block encoded bits to improve the detection reliability.
Observation 13:	Overlay sequence with bit segmentation can provide better performance by adapting the number of bits mapped to a sequence as in constellation, thus providing a trade-off between the coverage and performance.
Observation 14:	Bit segment-based mapping with fixed number of sequences, i.e., Alt-2, provides better configurability to NW by varying the number of sequences.
Observation 15:	Using bitmap of paged UE information with encoding provides efficient approach to map the overlay sequence over ON symbols of LP-WUS that uses either bitmap or codepoint based scheme.
Observation 16:	If the codepoint scheme is used for overlay sequence, early terminal may not be possible by IQ receivers until all MOs are processed with respect to overlay sequence length.
Observation 17:	If overlay sequence mapping uses segmented bits to carry the intended sequence on each ON OOK symbol, restricting to only 1 or 2 sequences instead of all sequence correlation may not benefit is extracting the channel coding benefits.
Observation 18:	Adding CRC bits to the subgroup information increases the number of information bits, thus increasing the code rate and effectively reducing the detection performance.
Observation 19:	Adding a known bit instead of CRC before encoding improves the detection performance as it can be used as side-information at the detector employed at LR.
Observation 20:	Depending on the channel conditions, LR may resort to raw codeword detection or channel decoding of LP-WUS to determine the respective information.
Observation 21:	As the traffic arrival rate increases for UEs, only all-UE wake-up sequence is transmitted, and thus requiring only one MO.
Observation 22:	Averaging timing estimates obtained from multiple LP-SSs with predefined periodicity, the RTC can assumed to be calibrated to an accuracy of  with the help of NCO.
Observation 23:	LP-SS detection is performed as sequence correlation and not as symbol-by-symbol OOK detection for timing synchronization. Thus, it does not matter what  value used for LP-SS if LR uses a sequence stored as LUT and use it for correlation at a desired sampling rate.
Observation 24:	The choice of  used for connected mode should not be associated with the  value used for LP-SS as it is used only for idle operational mode.
Observation 25:	Using same  value for both LP-WUS and LP-SS may not be efficient as the requirement for timing offset itself will be the accuracy of estimation.
Observation 26:	In case of M=1, length 6 provides better compromise over timing and RSRP estimation accuracy while reducing the system footprint.
Observation 27:	Analysing the sequences with M=2, length 12 provides a better compromise between timing and RSRP estimation accuracy without significant overhead.
Observation 28:	The sparse sequence proposed in SET2 is superior to SET1 from the timing estimation error only by a sample or two, which is insignificant while considering receiver imperfections.
Observation 29:	The timing estimation accuracy of SET1 vs SET2 sequences are comparable within a margin of 2 sample error between them, but due to similar power levels as LP-WUS, SET1 is preferrable.
Observation 30:	The detection accuracy can be improved by averaging the timing estimates over multiple LP-SS monitoring occasions, while ensuring the coherency of the channel fading.
Observation 31:	Using 320ms LP-SS periodicity together with the codeword detection of LP-WUS, we can avoid introducing additional overhead/signal design at the NW.
Observation 32:	Repeating the information bits before RM encoding ensures more rows from the Generator matrix to be chosen and thus improves detection reliability with the existing rate matching operation.
Observation 33:	Appending known bits to information bits before RM encoding provides enough codeword separation even after rate matching and avoid all-zero sequence even when the information bits are all zeros.
Observation 34:	Appending a fixed known bits to information bits before RM encoding leads to a different subset of codewords from the codeword space.
Observation 35:	By adopting three timing hypotheses that are separated by half the maximum timing error, the OOK detection performance can be improved without significant degradation compared to ideal.
Observation 36:	The impact of timing error on the OOK detection performance is dB worse than the one without any timing error under the presence of channel coding.

3GPP TSG-RAN WG1 Meeting #120bis	R1-2503014
Wuhan, China, April 7th-11th, 2025

Source:	Moderator (vivo)
Title:	Summary #1 of discussion on LP-WUS and LP-SS design    
Agenda Item:	9.6.1
Document for:	Discussion and Decision

Proposal 14
Before discussing the details on WUS_codepoint_CONNECTED in higher layer parameters list, following should be firstly discussed
Whether a codepoint corresponds to [one or more] UEs


R1-2502675 Sharp 
Proposal 1: No need to specify repetition after channel coding with rate matching for LP-WUS information. 
Proposal 2: Support CRC attachment after RM encoding.
Proposal 3: Consider the group size of different LP-WUS information within one LO in the LP-WUS design and apply different code rates accordingly.
Proposal 4：Support Lzc = 132 as the overlaid sequence length for M = 1.
Proposal 5: Support Option 1A, where no additional synchronization signal is required, and allow a smaller configurable periodicity for LP-SS.
Proposal 6: Consider two methods for configuring LP-WUS resources:
   - BWP-specific mode, where LP-WUS resources are configured per BWP.
   - Cell-specific mode, where LP-WUS resources are configured at the cell level.


R1-2502880 Nordic
Proposal-1: Set of root sequence indices and corresponding cyclic-shifts are configured to a UE according to table below. .

Proposal-2: Manchester coding is applied to every LP-WUS by default, i.e. irrespective of M and SCS. 

Proposal-3: To simplify LP-WUS design, support only payloads of 3 and 5bits for LP-WUS
take 32bit codeblock length as baseline.
consider the same LP-WUS length for 3 and 5 bit payloads.
for repetitions consider sequential reading from circular buffer.

Proposal-4: For information mapping to overlaid sequences, in RAN1#120b collect proposed mapping schemes from contributions and discuss KPIs.

Proposal-5: Length of binary sequence is , i.e. there are three different sequence length, one for each M.

Proposal-6: Our preference is Option 1A
	Option 1A: No additional sync signal, LP-SS periodicity =320ms
Additionally support at least one of [80ms,160ms] for M=4

R1-2502908 Lenovo
Proposal 1: Consider preamble transmission before LO when the offset between LP-SS and the starting of LO can be more than configured value. 

Proposal 2: UE can benefit from power consumption, when the preamble can be configured closer to the monitoring occasion containing codepoint corresponding to all subgroups in a LO

3GPP TSG-RAN WG1 Meeting #120bis	R1-2503015
Wuhan, China, April 7th-11th, 2025

Source:	Moderator (vivo)
Title:	Summary #2 of discussion on LP-WUS and LP-SS design    
Agenda Item:	9.6.1
Document for:	Discussion and Decision

Proposal 14
Before discussing the details on WUS_codepoint_CONNECTED in higher layer parameters list, following should be firstly discussed
Whether a codepoint corresponds to [one or more] UEs


R1-2502675 Sharp 
Proposal 1: No need to specify repetition after channel coding with rate matching for LP-WUS information. 
Proposal 2: Support CRC attachment after RM encoding.
Proposal 3: Consider the group size of different LP-WUS information within one LO in the LP-WUS design and apply different code rates accordingly.
Proposal 4：Support Lzc = 132 as the overlaid sequence length for M = 1.
Proposal 5: Support Option 1A, where no additional synchronization signal is required, and allow a smaller configurable periodicity for LP-SS.
Proposal 6: Consider two methods for configuring LP-WUS resources:
   - BWP-specific mode, where LP-WUS resources are configured per BWP.
   - Cell-specific mode, where LP-WUS resources are configured at the cell level.


R1-2502880 Nordic
Proposal-1: Set of root sequence indices and corresponding cyclic-shifts are configured to a UE according to table below. .

Proposal-2: Manchester coding is applied to every LP-WUS by default, i.e. irrespective of M and SCS. 

Proposal-3: To simplify LP-WUS design, support only payloads of 3 and 5bits for LP-WUS
take 32bit codeblock length as baseline.
consider the same LP-WUS length for 3 and 5 bit payloads.
for repetitions consider sequential reading from circular buffer.

Proposal-4: For information mapping to overlaid sequences, in RAN1#120b collect proposed mapping schemes from contributions and discuss KPIs.

Proposal-5: Length of binary sequence is , i.e. there are three different sequence length, one for each M.

Proposal-6: Our preference is Option 1A
	Option 1A: No additional sync signal, LP-SS periodicity =320ms
Additionally support at least one of [80ms,160ms] for M=4

R1-2502908 Lenovo
Proposal 1: Consider preamble transmission before LO when the offset between LP-SS and the starting of LO can be more than configured value. 

Proposal 2: UE can benefit from power consumption, when the preamble can be configured closer to the monitoring occasion containing codepoint corresponding to all subgroups in a LO

3GPP TSG-RAN WG1 Meeting #120bis	R1-2503082
Wuhan, China, April 7th-11th, 2025

Source:	Moderator (vivo)
Title:	Summary #3 of discussion on LP-WUS and LP-SS design    
Agenda Item:	9.6.1
Document for:	Discussion and Decision

Proposal 14
Before discussing the details on WUS_codepoint_CONNECTED in higher layer parameters list, following should be firstly discussed
Whether a codepoint corresponds to [one or more] UEs


R1-2502675 Sharp 
Proposal 1: No need to specify repetition after channel coding with rate matching for LP-WUS information. 
Proposal 2: Support CRC attachment after RM encoding.
Proposal 3: Consider the group size of different LP-WUS information within one LO in the LP-WUS design and apply different code rates accordingly.
Proposal 4：Support Lzc = 132 as the overlaid sequence length for M = 1.
Proposal 5: Support Option 1A, where no additional synchronization signal is required, and allow a smaller configurable periodicity for LP-SS.
Proposal 6: Consider two methods for configuring LP-WUS resources:
   - BWP-specific mode, where LP-WUS resources are configured per BWP.
   - Cell-specific mode, where LP-WUS resources are configured at the cell level.


R1-2502880 Nordic
Proposal-1: Set of root sequence indices and corresponding cyclic-shifts are configured to a UE according to table below. .

Proposal-2: Manchester coding is applied to every LP-WUS by default, i.e. irrespective of M and SCS. 

Proposal-3: To simplify LP-WUS design, support only payloads of 3 and 5bits for LP-WUS
take 32bit codeblock length as baseline.
consider the same LP-WUS length for 3 and 5 bit payloads.
for repetitions consider sequential reading from circular buffer.

Proposal-4: For information mapping to overlaid sequences, in RAN1#120b collect proposed mapping schemes from contributions and discuss KPIs.

Proposal-5: Length of binary sequence is , i.e. there are three different sequence length, one for each M.

Proposal-6: Our preference is Option 1A
	Option 1A: No additional sync signal, LP-SS periodicity =320ms
Additionally support at least one of [80ms,160ms] for M=4

R1-2502908 Lenovo
Proposal 1: Consider preamble transmission before LO when the offset between LP-SS and the starting of LO can be more than configured value. 

Proposal 2: UE can benefit from power consumption, when the preamble can be configured closer to the monitoring occasion containing codepoint corresponding to all subgroups in a LO

3GPP TSG-RAN WG1 Meeting #120bis	R1-2503083
Wuhan, China, April 7th-11th, 2025

Source:	Moderator (vivo)
Title:	Summary #4 of discussion on LP-WUS and LP-SS design    
Agenda Item:	9.6.1
Document for:	Discussion and Decision

Proposal 14
Before discussing the details on WUS_codepoint_CONNECTED in higher layer parameters list, following should be firstly discussed
Whether a codepoint corresponds to [one or more] UEs


R1-2502675 Sharp 
Proposal 1: No need to specify repetition after channel coding with rate matching for LP-WUS information. 
Proposal 2: Support CRC attachment after RM encoding.
Proposal 3: Consider the group size of different LP-WUS information within one LO in the LP-WUS design and apply different code rates accordingly.
Proposal 4：Support Lzc = 132 as the overlaid sequence length for M = 1.
Proposal 5: Support Option 1A, where no additional synchronization signal is required, and allow a smaller configurable periodicity for LP-SS.
Proposal 6: Consider two methods for configuring LP-WUS resources:
   - BWP-specific mode, where LP-WUS resources are configured per BWP.
   - Cell-specific mode, where LP-WUS resources are configured at the cell level.


R1-2502880 Nordic
Proposal-1: Set of root sequence indices and corresponding cyclic-shifts are configured to a UE according to table below. .

Proposal-2: Manchester coding is applied to every LP-WUS by default, i.e. irrespective of M and SCS. 

Proposal-3: To simplify LP-WUS design, support only payloads of 3 and 5bits for LP-WUS
take 32bit codeblock length as baseline.
consider the same LP-WUS length for 3 and 5 bit payloads.
for repetitions consider sequential reading from circular buffer.

Proposal-4: For information mapping to overlaid sequences, in RAN1#120b collect proposed mapping schemes from contributions and discuss KPIs.

Proposal-5: Length of binary sequence is , i.e. there are three different sequence length, one for each M.

Proposal-6: Our preference is Option 1A
	Option 1A: No additional sync signal, LP-SS periodicity =320ms
Additionally support at least one of [80ms,160ms] for M=4

R1-2502908 Lenovo
Proposal 1: Consider preamble transmission before LO when the offset between LP-SS and the starting of LO can be more than configured value. 

Proposal 2: UE can benefit from power consumption, when the preamble can be configured closer to the monitoring occasion containing codepoint corresponding to all subgroups in a LO

3GPP TSG-RAN WG1 Meeting #120bis	R1-2503097
Wuhan, China, April 7th-11th, 2025

Source:	Moderator (vivo)
Title:	Summary #5 of discussion on LP-WUS and LP-SS design    
Agenda Item:	9.6.1
Document for:	Discussion and Decision

Proposal 14
Before discussing the details on WUS_codepoint_CONNECTED in higher layer parameters list, following should be firstly discussed
Whether a codepoint corresponds to [one or more] UEs


R1-2502675 Sharp 
Proposal 1: No need to specify repetition after channel coding with rate matching for LP-WUS information. 
Proposal 2: Support CRC attachment after RM encoding.
Proposal 3: Consider the group size of different LP-WUS information within one LO in the LP-WUS design and apply different code rates accordingly.
Proposal 4：Support Lzc = 132 as the overlaid sequence length for M = 1.
Proposal 5: Support Option 1A, where no additional synchronization signal is required, and allow a smaller configurable periodicity for LP-SS.
Proposal 6: Consider two methods for configuring LP-WUS resources:
   - BWP-specific mode, where LP-WUS resources are configured per BWP.
   - Cell-specific mode, where LP-WUS resources are configured at the cell level.


R1-2502880 Nordic
Proposal-1: Set of root sequence indices and corresponding cyclic-shifts are configured to a UE according to table below. .

Proposal-2: Manchester coding is applied to every LP-WUS by default, i.e. irrespective of M and SCS. 

Proposal-3: To simplify LP-WUS design, support only payloads of 3 and 5bits for LP-WUS
take 32bit codeblock length as baseline.
consider the same LP-WUS length for 3 and 5 bit payloads.
for repetitions consider sequential reading from circular buffer.

Proposal-4: For information mapping to overlaid sequences, in RAN1#120b collect proposed mapping schemes from contributions and discuss KPIs.

Proposal-5: Length of binary sequence is , i.e. there are three different sequence length, one for each M.

Proposal-6: Our preference is Option 1A
	Option 1A: No additional sync signal, LP-SS periodicity =320ms
Additionally support at least one of [80ms,160ms] for M=4

R1-2502908 Lenovo
Proposal 1: Consider preamble transmission before LO when the offset between LP-SS and the starting of LO can be more than configured value. 

Proposal 2: UE can benefit from power consumption, when the preamble can be configured closer to the monitoring occasion containing codepoint corresponding to all subgroups in a LO

3GPP TSG-RAN WG1 Meeting #120bis	R1-2503098
Wuhan, China, April 7th-11th, 2025

Source:	Moderator (vivo)
Title:	Summary #6 of discussion on LP-WUS and LP-SS design    
Agenda Item:	9.6.1
Document for:	Discussion and Decision

Proposal 14
Before discussing the details on WUS_codepoint_CONNECTED in higher layer parameters list, following should be firstly discussed
Whether a codepoint corresponds to [one or more] UEs


R1-2502675 Sharp 
Proposal 1: No need to specify repetition after channel coding with rate matching for LP-WUS information. 
Proposal 2: Support CRC attachment after RM encoding.
Proposal 3: Consider the group size of different LP-WUS information within one LO in the LP-WUS design and apply different code rates accordingly.
Proposal 4：Support Lzc = 132 as the overlaid sequence length for M = 1.
Proposal 5: Support Option 1A, where no additional synchronization signal is required, and allow a smaller configurable periodicity for LP-SS.
Proposal 6: Consider two methods for configuring LP-WUS resources:
   - BWP-specific mode, where LP-WUS resources are configured per BWP.
   - Cell-specific mode, where LP-WUS resources are configured at the cell level.


R1-2502880 Nordic
Proposal-1: Set of root sequence indices and corresponding cyclic-shifts are configured to a UE according to table below. .

Proposal-2: Manchester coding is applied to every LP-WUS by default, i.e. irrespective of M and SCS. 

Proposal-3: To simplify LP-WUS design, support only payloads of 3 and 5bits for LP-WUS
take 32bit codeblock length as baseline.
consider the same LP-WUS length for 3 and 5 bit payloads.
for repetitions consider sequential reading from circular buffer.

Proposal-4: For information mapping to overlaid sequences, in RAN1#120b collect proposed mapping schemes from contributions and discuss KPIs.

Proposal-5: Length of binary sequence is , i.e. there are three different sequence length, one for each M.

Proposal-6: Our preference is Option 1A
	Option 1A: No additional sync signal, LP-SS periodicity =320ms
Additionally support at least one of [80ms,160ms] for M=4

R1-2502908 Lenovo
Proposal 1: Consider preamble transmission before LO when the offset between LP-SS and the starting of LO can be more than configured value. 

Proposal 2: UE can benefit from power consumption, when the preamble can be configured closer to the monitoring occasion containing codepoint corresponding to all subgroups in a LO

3GPP TSG-RAN WG1 Meeting #120bis	R1-2503099
Wuhan, China, April 7th-11th, 2025

Source:	Moderator (vivo)
Title:	Final summary of discussion on LP-WUS and LP-SS design    
Agenda Item:	9.6.1
Document for:	Discussion and Decision

Proposal 14
Before discussing the details on WUS_codepoint_CONNECTED in higher layer parameters list, following should be firstly discussed
Whether a codepoint corresponds to [one or more] UEs


R1-2502675 Sharp 
Proposal 1: No need to specify repetition after channel coding with rate matching for LP-WUS information. 
Proposal 2: Support CRC attachment after RM encoding.
Proposal 3: Consider the group size of different LP-WUS information within one LO in the LP-WUS design and apply different code rates accordingly.
Proposal 4：Support Lzc = 132 as the overlaid sequence length for M = 1.
Proposal 5: Support Option 1A, where no additional synchronization signal is required, and allow a smaller configurable periodicity for LP-SS.
Proposal 6: Consider two methods for configuring LP-WUS resources:
   - BWP-specific mode, where LP-WUS resources are configured per BWP.
   - Cell-specific mode, where LP-WUS resources are configured at the cell level.


R1-2502880 Nordic
Proposal-1: Set of root sequence indices and corresponding cyclic-shifts are configured to a UE according to table below. .

Proposal-2: Manchester coding is applied to every LP-WUS by default, i.e. irrespective of M and SCS. 

Proposal-3: To simplify LP-WUS design, support only payloads of 3 and 5bits for LP-WUS
take 32bit codeblock length as baseline.
consider the same LP-WUS length for 3 and 5 bit payloads.
for repetitions consider sequential reading from circular buffer.

Proposal-4: For information mapping to overlaid sequences, in RAN1#120b collect proposed mapping schemes from contributions and discuss KPIs.

Proposal-5: Length of binary sequence is , i.e. there are three different sequence length, one for each M.

Proposal-6: Our preference is Option 1A
	Option 1A: No additional sync signal, LP-SS periodicity =320ms
Additionally support at least one of [80ms,160ms] for M=4

R1-2502908 Lenovo
Proposal 1: Consider preamble transmission before LO when the offset between LP-SS and the starting of LO can be more than configured value. 

Proposal 2: UE can benefit from power consumption, when the preamble can be configured closer to the monitoring occasion containing codepoint corresponding to all subgroups in a LO