3GPP TSG-RAN WG2 Meeting #130	R2-2503390
St Julian’s, Malta, 19-23 May 2025	

Agenda Item:	8.18.2
Source:	NEC
Title:	Configuration to support LTE-based 5G Broadcast
Document for:	Discussion, Decision

Conclusion and Proposal
We have the following proposals:

Proposal 1: RRC signalling is employed for configuring time interleaved transmission (i.e., the values of M and N).
Proposal 2: Per MBMS session is supported for configuring time interleaved transmission (i.e., the values of M and N).

3GPP TSG-RAN WG2 Meeting #130	R2-2503506
St. Julian’s, Malta, May 19th - 23rd, 2025

Agenda item:		8.18.2
Source:		Samsung
Title:	Configuration and scheduling aspects for LTE-based 5G Broadcast Phase 2
Document for:	Discussion & Decision
1 

Conclusion
Based on the discussion above, request RAN2 to consider the following proposals:
Proposal 1: Co-existence for legacy and R19 transmission and UEs is achieved with defining R19 PMCHs to cater to Time Interleaving based configurations, scheduling and transmissions in addition to legacy PMCHs.

Proposal 2: Wait for RAN1 decision on the configuration for the time interleaving transmission and accordingly, incorporate in to the configuration signaling.

Proposal 3: RAN2 to incorporate an extended set of configurable periodicities for MCH scheduling period for R19 PMCHs once RAN1 provides the relevant set of values.

Proposal 4: Wait for RAN1 to decide on UE behaviour in case of residual mismatch even after new periodicities are adopted, taking into account the amount of subframe available at the end of the periodicity and accordingly, if needed, RAN2 specify the MAC protocol.

Proposal 5: RAN2 to adopt and specify minimal multiplexing enhancements for MCH reception that are applied only for scheduling of R19 PMCHs based MTCHs and include:
Not allowing multiplexing of two MTCHs in same subframe 
Not applying Time interleaving to subframe carrying MSI/eMSI/MCCH
Not allowing multiplexing of MTCH with MSI/eMSI/MCCH in a sub-frame due to Time interleaving difference
Inserting and/ interpreting padding to account for remaining portion of the subframe in above scenarios 

Proposal 6: RAN2 to specify the HARQ handling for Rel-19 5G Broadcast with regard to differentiating new transmission and retransmission/repetition, allowing for soft combining and addressing HARQ feedback generation aspects.

Proposal 7: Wait for RAN1 LS for capability parameters and accordingly, RAN2 specify the UE capability information signalling for Rel-19 5G Broadcast.
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3GPP TSG-RAN WG2 Meeting #130	                              R2-2504075
St. Julians, Malta, 19 - 23 May 2025

Agenda Item:	8.18.2
Source:	Huawei, HiSilicon
Title:	Discussion on time-frequency interleavers for MBMS
Document for: Discussion and Decision
1	

Conclusion
Based on the above discussion we have the following observation and proposals: 
Signalling to support time-frequency interleaving：
Observation 1: The time interleaving is only applied to MTCH, not for MCCH and MSI MAC CE.
Observation 2: The eNB should indicate time interleaving parameters M and N to UE, where parameter N indicates the TBS scaling factor N, and parameter M indicates the interval between two transmissions of the same TB.
Proposal 1: A new Rel-19 field PMCH-InfoListExt-r19 should be introduced to indicate the time interleaving parameters. The details, e.g. per PMCH or per session configuration, are pending RAN1 discussion.
Proposal 2: UE should be indicated by eNB whether the frequency interleaving is enabled or not. The details, e.g., eNB indicates this explicitly or implicitly via the presence of frequency interleaving parameters, are pending RAN1 discussion.
Impact on cell reselection
Proposal 3: UE supporting time-frequency interleaving should prioritize the cells enabling time-frequency interleaving while legacy UE shouldn’t. 
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3GPP TSG-RAN2 Meeting #130	R2-2504260
Malta, May 19-23, 2025	

Agenda Item:	8.18.2
Work Item:	LTE_terr_bcast_Ph2-Core
Source: 	Qualcomm Incorporated, EBU
Title: 	RAN2 impacts to support time-frequency interleavers for LTE-based 5G Broadcast Phase 2
Document for:	Discussion/Decision

Summary 
Based on the discussion above, we have the following proposals:
Proposal 1:	Wait for RAN1 for the down-selection regarding the configuration for time interleaving transmission.
Proposal 2:	Wait for RAN1 for the candidate values of the new MCH scheduling period(s).
Proposal 3:	Introduce a field to indicate TBS scaling factor (i.e. N) with candidate values {2,4,8,16,ffs}.
Proposal 4:	Introduce a field to indicate the separation between two transmissions of the same TB (i.e. M) with candidate values {4,8,16,32,ffs}.
Proposal 5:	Presence of the parent IE containing fields for N and M indicates time interleaving is enabled.
Proposal 6:	Introduce a flag to indicate whether frequency interleaving for MTCH is enabled.
Proposal 7:	Postpone the discussion about UE capabilities to next meeting.
Proposal 8:	ASN.1 example given in section 5 can be taken as baseline for LTE RRC CR.

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