Summary Report from 3GPP plenaries (mainly RAN) #100 (Taipei, 12 - 16 June) and #101 (Bangalore, India, 11 - 15 Sept. 2023)

Hans van der Veen, NEC Laboratories Europe GmbH

 

General

This report covers the June and September 3GPP plenaries and (where relevant) June Rel-19 Workshop, as consolidated report. Since there was 100% time overlap between RAN and SA, this report covers mostly the status in RAN only.

Rel-18

-     No new Rel-18 WIs/SIs were approved except spectrum-related and conformance testing

Rel-19

-     In June and September, the possible content of Rel-19 was discussed (only high level firm decisions, but with the direction for all potential topics becoming clearer). The work package will only be decided firmly in December.

 

Rel-18

Rel-18 Planning and progress (Stage 2, SA3 and RAN1 work frozen)

Stage 1: frozen December 2021 without exceptions

RAN1/2/3 work package: approved December 2021

RAN4 work package: approved March 2022

Stage 2: frozen June 2023

SA3: frozen September 2023

RAN1: frozen September 2023

RAN2/3/4 core functionality: freezing target December 2023

Stage 3: freezing target March 2024

ASN.1 and open APIs: freezing target June 2024 (review date March 2024)

RAN4: freezing target June 2024

 

Closed Rel-18 Work Items and Study Items (excluding spectrum-related and conformance testing)

Rel-18 NR

-     SI: Study on NR base station (BS) RF requirement evolution

-     SI: Study on Ambient IoT (Internet of Things) in RAN

-     SI: Study on enhancement for sub-1GHz band combinations

-     Core: Enhanced NR support for high speed train scenario in frequency range 2 (FR2)

Rel-18 LTE

-     Perf.: NB-IoT (Narrowband IoT)/eMTC (enhanced Machine Type Communication) core & performance requirements for Non-Terrestrial Networks (NTN)

-     Core: New bands and bandwidth allocation for 5G terrestrial broadcast - part 2

 

Rel-18 RAN Work Item Summaries (descriptions of features in the release after the work has actually finished)

-     RP-231731 NR support for high speed train scenario in frequency range 2 (FR2)

 

Rel-18 NR: Ambient IoT (Summary: RP-232689; Approved TR: RP-232695)

RAN completed the RAN-level SI including approval of TR 38.848.

 

Rel-18 3GPP submission to IMT-2020 Satellite (Agreed WF: RP-231457; Approved Revised SID: RP-231296)

RAN endorsed the following structure for IMT-2020 satellite submission:

• RIT (Radio Interface Technology): NR NTN

• SRIT (Set of Radio Interface Technologies), consisting of the following component RITs:

– Component RIT#1: NR NTN

– Component RIT#2: IoT NTN (both NB IoT NTN & eMTC NTN)

 

Rel-18 NR: Enhanced support of reduced capability NR devices (Approved revised WID: RP-232671)

The peak rate target is 10 Mbps regardless of what optional features the UE may support.

 

Rel-18 NR: Expanded and Improved NR Positioning (Approved revised WID: RP-232670)

The scope was reduced as follows:

-     Supported positioning methods: For SL-TDOA (sidelink time difference of arrival), RAN2 will not work on procedures for synchronization of the anchor UEs. RAN2 can discuss and implement agreed RAN1 parameters related to synchronization

-     Supported scenario: Specify the protocol and procedures for SL positioning between UEs and between UEs and a single Location Management Function (LMF) for in coverage scenario only, including joint PC5-Uu scenarios

-     Localization target: Single target UE only for signalling (multiple target UEs not precluded but no optimization)

-     Supported cast type for signalling: Unicast only (i.e. without broadcast/groupcast, no session-less)

Rel-18 NR: UAV (Uncrewed Aerial Vehicles) (LSin: RP-231529)

RAN decided not to work on no-transmit zones (NTZ) in Rel-18 based on the incoming LS from SA2.

 

Rel-18 NR: NTN (Summary: RP-232665; Endorsed WF: RP-232694; Approved revised WID: RP-232669)

RAN4 shall work on the definition of RRM requirements considering the following cases: Case-1: Stationary UE for GSO; Case-2: Stationary UE for LEO; Case-3: Mobile UE for GSO.

 

Rel-18 NR: XR (eXtended Reality) enhancements for NR (Endorsed summary: RP-232657; Endorsed WF: RP-231820)

Handheld smartphone UEs are excluded from any 2Rx relaxation for XR wearables.

The default for non-RedCap XR-wearable UEs is 4Rx (for frequency bands where 4Rx is mandated).

A non-RedCap XR-wearable UE can be considered for 2Rx relaxation (for frequency bands where 4Rx is mandated) if and only if:

-     Intended to be worn on the human head;

-     When in use, is intended to be supported only by/behind the ears and by a nose-bridge resulting in a constrained form factor with limited volume available for Rx chains;

-     No other relaxation is being considered apart from number of Rx antennas

 

Rel-18 NR: AI/ML for NG-RAN (Approved Revised WID: RP-231159)

The WI was extended to December.

 

Approved Rel-18 Work Items and Study Items (excluding spectrum-related and conformance testing)

-     <none>

 

Rel-19

Rel-19 Planning (Stage 1 normative work 92%; 1st part (SA/CT) work package approved; Stage 3 freeze September 2025)

RAN Workshop: took place in June 2023

SA Workshop: took place in June 2023

Stage 1: freeze December 2023 (92% normative work completion reached by September 2023)

SA Stage 2 work package: complete package planned to be approved December 2023 (1st part (SA/CT) by September 2023)

RAN1/2/3 work package: planned to be approved December 2023

RAN4 work package: planned to be approved March 2024

Stage 2: freezing target December 2024

RAN1: freezing target June 2025

RAN2/3/4 core functionality: freezing target September 2025

Stage 3: freezing target September 2025

ASN.1 and open APIs: freezing target December 2025

RAN4: freezing target December 2025

 

Rel-19 RAN1/2/3 work package definition (Endorsed status: RP-231540)

Roughly half of 1200 (!) input documents submitted to RAN#101 was related to Rel-19. The following list of potential Rel-19 topics was endorsed. Note: RIS was explicitly excluded from Rel-19 during the discussions, despite significant operator support.

 

List of Potential RAN1-led Items for Subsequent Discussion till RAN#102

Index

Title

1

AI (Artificial Intelligence)/ML (Machine Learning) for Air interface

2

MIMO Evolution

3

Duplex Evolution

4

Ambient IoT*

5

Network energy savings

6

LP-WUS/WUR

7

ISAC & Exploring study in new spectrum (7-24 GHz) **

* Further discussion SI only or SI à WI

** May start as a RAN-level study item first. For the new spectrum, focusing on channel modeling only. For ISAC, further discus channel modeling only or additionally techniques

In addition to the above, RAN1 may have room up to 2 RAN1-led small projects

List of Potential RAN2-led Items for Subsequent Discussion till RAN#102

Index

Title

1

Mobility Enhancements

2

Enhancements for XR

3

NTN (Non-Terrestrial Networks) evolution for NR

4

NTN (Non-Terrestrial Networks) evolution for IoT

5

AI/ML for Air interface SI (Mobility)

 

[RAN1-led] Ambient IoT

[RAN1-led] AI/ML for Air interface

In addition to the above, RAN2 may have room up to 3 RAN2-led small projects

 

List of Potential RAN3-led Items for Subsequent Discussion till RAN#102

Index

Title

1

AI/ML for NG-RAN

2

SON/MDT Enhancements

3

Additional Topological Enhancements

 

[RAN1-led] Ambient IoT

In addition to the above, RAN3 may not have room for additional RAN3-led projects

 

Additional Considerations

  • Additional Candidate Topics for further consideration during RAN#101 and till RAN#102
    • Multi-carrier Enhancements
    • Coverage Enhancements
    • Positioning Enhancements
    • SL Evolution
    • NCR
    • SL Relay Enhancements
    • UAV/UAM
    • MU-SIM
    • Broadcast/multicast
    • UE aggregation, collaboration, and backup
    • Lean protocol stack/High speed packetization/Layer 2 UP enhancements
    • QoE
    • Others

 

In summary:

Categorization of topics based on WS contributions

 

The following documents describe the latest status for each topic (note: they have not been endorsed, but still give very strong indications of the direction of the discussion on each topic towards the December approval of the work package. For more details, see the Annex of this report.

 

-     RP-232611 RAN1 topic AI (Artificial Intelligence)/ML (Machine Learning) for Air interface

-     RP-232622 RAN2 topic AI/ML for Air Interface SI (Mobility)

-     RP-232612 RAN1 topic MIMO Evolution

-     RP-232613 RAN1 topic Duplex Evolution

-     RP-232614 RAN1 topic Ambient IoT

-     RP-232615 RAN1 topic Network Energy Savings

-     RP-232618 RAN2 topic Mobility Enhancements

-     RP-232610 RAN2 topic NTN for NR

-     RP-232621 RAN2 topic NTN for IoT

-     RP-232619 RAN2 topic Enhancements for XR

-     RP-232623 RAN3 topic AI/ML for NG-RAN

-     RP-232624 RAN3 topic SON/MDT Enhancements

-     RP-232617 RAN1 topic ISAC & Exploring Study in New spectrum (7-24GHz)

-     RP-232626 RAN1 additional topics

-     RP-232616 RAN1 topic LP-WUS/WUR

-     RP-232627 RAN2 additional topics

-     RP-232628 RAN3 additional topics

-     RP-232625 RAN3 topic Additional Topological Enhancements

 

Rel-19 RAN work package definition

RAN4 topics had not been discussed at the RAN Rel-19 Workshop in June. A large number of presentations were given, but without any conclusions so far. The December plenary meeting will continue discussing candidate topics for RF/OTA and candidate topics for Demod/RRM, but no spectrum-related topics. The RAN4 work package will be decided in March 2024.

 

6G and IMT-2030 Planning (ITU-R WP5D LSin: RP-231518)

Companies made proposals on how to handle 6G and IMT-2030, but no decisions were taken. Frequent proposals included a 6G Workshop in 2024 or 2025, and defining two releases (Rel-20 and Rel-21), with Rel-21 the basis for IMT-2030 submission. ITU-R WP5D plans to submit [IMT.FRAMEWORK FOR 2030 AND BEYOND] for approval to the September ITU-R SG5 meeting:

 

 

 

 

Annex: Status of Rel-19 discussion (not endorsed)

-     RP-232611 RAN1 topic AI (Artificial Intelligence)/ML (Machine Learning) for Air interface
• Consider support single sided models for (1) Positioning; (2) Beam management for DL Tx prediction in both UE-sided and NW sided model,
• Consider support of single sided model for CSI prediction, if it is recommended to proceed with normative work
• Consider support two-sided model for CSI compression, if it is recommended to proceed with normative work
• Consider support the necessary/recommended LCM components for selected sub use cases
• RAN4 requirements and test cases for AI/ML enabled features

 

-     RP-232622 RAN2 topic AI/ML for Air Interface SI (Mobility)
For mobility under connected mode, the potential scopes/directions of the study item include:
• Type of mobility
• L3-based mobility and L1/L2-triggered mobility (LTM) are both considered
• HO optimization in Network side [/UE side], including
• Candidate/target cell prediction in L3-based mobility, or, candidate/target beam(s) and cell(s) prediction in LTM
• RRM measurement and event prediction, including
• Beam-level measurement prediction
• Cell-level measurement prediction, e.g., using intra-frequency measurement results to forecast the RRM measurement of inter-frequency/inter-RAT cells
• HO failure/RLF prediction
• Measurement events prediction
• LCM framework and others
• The conclusions in Rel-18 AI/ML study should be used as baseline
• Other impacts are further studied
• [UE RRM enhancement, RAN4]
• Note 1: no intention to change the existing framework for the mobility under connected mode
• Note 2: In the SID, target performance metrics and impacts should be clarified
• Note 3: Avoid overlap work with RAN3

 

-     RP-232612 RAN1 topic MIMO Evolution
Topic 1: Beam management enhancements to reduce overhead/latency through UE-initiated/event-driven beam management
• Objective 1. Signalling/mechanism to facilitate UE-initiated beam management procedure including UE-initiated beam reporting/switch
Topic 2: Enhancements to CSI framework to support > 32 (64/128) CSI-RS ports
• Objective 1: Type I codebook enhancements to support > 32 CSI-RS ports
• Objective 2: Type II codebook enhancements to support > 32 CSI-RS ports
• Objective 3: Hybrid beamforming enhancements (CRI based reporting enhancements)
• Note 1: Extension of legacy codebooks and legacy CSI-RS resources
• Note 2: Objective 3 may require further study or clarification.
Topic 3: CJT/DL multi-TRP enhancements
• Objective 1: UE-assisted calibration reporting of delay and frequency/phase offsets for CJT with non-ideal synchronization and backhaul
• Note: Assume legacy CSI-RS design and standalone aperiodic reporting on PUSCH.
Topic 4: UL enhancements
• Objective 1: STxMP enhancements (e.g. Simultaneous TX of PUCCH and PUSCH, Asymmetric panel implementations, mDCI PUCCH + PUCCH, STxMP with up to rank 8, Coherent SFN STxMP)
• Objective 2: Enhancements for UL 3Tx including 3Tx for UL codebook and non-codebook based transmission
Topic 5: Enhancement for asymmetric downlink S-TRP/UL M-TRP scenario assuming intra-band intra-cell non-co-located M-TRP scenarios without changing existing cell definition or defining a new cell
• Objective 1: Extension of Rel-18 2TA mDCI to sDCI assuming legacy PRACH resources
• Objective 2: Separate UL power control for SRS only to downlink S-TRP from SRS to UL M-TRP and introduce path loss measurement to uplink M-TRP
Topic 6: 6Rx/8Rx UE enhancements with lower complexity utilizing two segments of 3/4 Rx antenna units up to 8-layer DL Tx based on legacy codebook and legacy codeword to layer mapping
• Objective 1: SRS antenna port grouping, CSI and codeword association to the segments of receive antenna.

 

-     RP-232613 RAN1 topic Duplex Evolution
Whether to have parallel SI on UE side SBFD operation with normative work on gNB side SBFD operation?
• Majority of companies do not prefer to have parallel SI on UE side SBFD operation
• There is a suggestion that the study on UE side SBFD can be started in later phase of Rel-19 if normative work on gNB side SBFD can be completed before the end of Rel-19
Potential normative work on gNB side SBFD operation within a TDD carrier should include at least following points that can be considered as starting point for WID objective discussion
• Indication of time and frequency domain locations of SBFD subbands to UEs
• UE transmission and reception behavior and procedures in SBFD symbols and/or non-SBFD symbols related to SBFD operation at gNB
• RF requirements for SBFD operation at gNB
• Above is just general description, and for WID objective descriptions, some clarifications would be necessary.
• Regarding “semi-static configuration” of frequency domain locations of SBFD subbands, “semi-static configuration” of frequency domain locations of SBFD sub-bands is anyway necessary.
• At least adjacent channel coexistence between two operators should be considered as a minimum.
Whether normative work on Duplex evolution in Rel-19 should include at least either gNB-to-gNB co-channel CLI handling or UE-to-UE co-channel CLI handling?
• There are divergent views on minimum necessary objective related to co-channel CLI handling for Rel-19 Duplex Evolution WI.

 

-     RP-232614 RAN1 topic Ambient IoT

Possible list of objectives for a WG-level study item

  • Evaluations and remaining feasibility assessments
  • Device architecture and characteristics
  • Evaluation methodology and assumptions
  • Design target evaluations
  • Coexistence evaluations
    • Physical layer study on:
  • Waveform and multiple access
  • Frame structure and numerology
  • Modulation and channel coding
  • Physical layer signals/channels
  • Physical layer procedures including initial access and mobility, scheduling, (H)ARQ, power control, etc
    • Higher layers study on:
  • Compact protocol stack and lightweight signaling procedure, including mobility aspects
    • Control plane functionalities, including CN connectivity
    • User plane functionalities
    • Security aspects (*Note: This does not necessarily mean security has RAN impact)
      • RAN3 aspects for study:
        • Enabling necessary CN-RAN signalling
        • RAN architecture aspects, if any
      • RAN4 aspects for study:
        • Feasibility study of BS/UE/device architectures
        • Link budget study
        • Coexistence analysis
        • RRM

 

-     RP-232615 RAN1 topic Network Energy Savings
Justification for further work on network energy savings
• Many techniques evaluated in TR 38.864 were shown to bring substantial NES gains, but were not included in Rel-18 due to limited time and capacity in RAN WGs.
• Rel-18 has focused primarily on RRC Connected, user specific signals and channels, and low load scenarios.
• Rel-19 could address network energy savings in different deployment scenarios and operating points than specified in Rel-18. e.g. Rel-18 NES limits SSB-less operation for SCell(s) to inter-band cases for FR1 co-located scenarios.
Summary of the main directions proposed at RAN#101
One direction was proposed by almost all sources, with a few open questions
• On-demand SSB transmission and on-demand SIB1 transmission (documented in TR38.864). Focus:
- On-demand SIB1/[SSB] for idle UEs
- On-demand SSB ([and possibly other DL signals]) for Scell for connected UEs
Another group (G1) of proposals were contributed by nearly half of the sources (12~13)
• [SSB]/SIB1-less operation in multi-carrier scenario for (documented in TR38.864)
• [SSB]/SIB1-less for non-anchor NES cell for UEs in IDLE/INACTIVE state, where it is assumed that another carrier (an anchor cell) is available for the UE
A second group (G2) of proposals was contributed by 5~10 sources
• Cell DRX/DTX for UEs in idle/inactive modes (as an extension of Rel-18 cell DRX/DTX)
Multi-TRP adaptation mechanisms
• Proposals are fragmented and the scope could be very broad
• Details could include measurements, CSI feedback, power control, PDCCH/PUCCH/PUSCH/PDSCH repetition, single-DCI based scheduling, multi-DCI based scheduling, SRS transmission, TCI configuration, beam management, beam failure recovery, radio link monitoring, cell (re)selection, handover, initial access, etc.
Aspects discussed but not specified in Rel-18
• Proposals are fragmented and very generic, including BM/TCI enhancements, UE complexity/CSI payload reduction, PUCCH resource adaptation
A third group (G3) of proposals was contributed by just one or two sources, in many cases such techniques were not studied in Rel-18
Summary of the RAN3-led directions proposed at RAN#101
A group (G4) of proposals is looking at network coordination aspects, but proposals are rather fragmented so far (mostly single company proposals). Some proposals may impact RAN2 and RAN1.
Coordination with SA
• One source proposed to include objectives to address aspects discussed in SA:
• SA work wants to understand energy consumption on a:
- per UE basis
- per UE per PDN connection basis;
- per UE per PDN connection per QoS flow basis.
• As the large majority of energy consumption is in the RAN, early Rel 19 RAN WG co-operation is needed, e.g.
- RAN 1 for guidance on whether reporting can be based on e.g. the sum of number of resource blocks*TTI*transmit power.
- RAN 2 on the (in)feasibility of per PDN, and per PDN per QoS flow reporting for a UE.
- RAN 3 on a reporting framework (e.g similar to “secondary RAT data volume reporting”).
It was not clear to the moderator whether this activity would be triggered by SA, or whether this would be discussed as an independent task for RAN in a RAN-led work item.

 

-     RP-232618 RAN2 topic Mobility Enhancements

Based on the RAN#101 offline discussion the following objectives should be agreeable:

  • Specify support for inter -CU Layer 2 Mobility (LTM)
    • Next level questions still to be discussed/decided:
      • Whether to support cases where CU is acting as MN, and when CU is acting SN?
      • For case where CU is acting as SN, whether it is support for EN-DC and/or NR-DC?
      • In answering the above questions, focus should be practical deployments.
  • Measurements related enhancements for purpose of supporting LTM:
    • Specify event triggered L1 measurement reporting for triggering LTM
    • Specify support for CSI-RS measurements for LTM procedures and enable CSI-RS based beam management and/or other physical layer operations on candidate cells before LTM

During the RAN#101 offline discussion there was strong interest in the following

  • Support of conditional mobility (including set of candidate cells, UE evaluated mobility conditions, ability for UE to perform subsequent mobility procedures without need for RRC configuration) along with short mobility interruption time (similar to that achievable with LTM).
    •     Next Step question to consider the most appropriate approach to achieve this aim. For example, by specifying conditional triggering of LTM, or specifying support of Early TA or RACHless (as defined for LTM) to be used as part of layer 3 CHO, or possibly other approaches. If this questions cannot be concluded during the Rel-19 scoping discussion then it may be possible to start with a RAN2 study phase.

During RAN#101 offline discussion the following were agreed to be reviewed again at RAN#102 with consideration to the outcome of the Rel-18 work item.

  • NR-DC cases supported by LTM. Note the following common understanding from the offline: LTM is important for MCG only case. In case of NR-DC then LTM on the SCG is the important case (e.g. in FR2), followed by LTM in MCG with SCG configured (SCG unchanged by MCG LTM)

 

 

 

-     RP-232610 RAN2 topic NTN for NR
Based on the offline discussion the following potential focus objectives have been identified:
• Coverage enhancements for Downlink
• Coverage enhancements for Uplink
• Regenerative payload
• Mobility enhancements
• Enhanced GNSS Operation
• Uplink capacity / throughput enhancement
• Robust Notification/Alert
• MBS via NTN (->) Broadcast only for NGSO
• REDCAP

 

-     RP-232621 RAN2 topic NTN for IoT
The WI shall be an LTE WI. The moderator proposed to consider initially the following objectives to the offline based on the submission assessment provided:
• Store & Forward
• Capacity enhancements
• 5GC supporting IoT-NTN
• NTN/TN Mobility enhancements

 

-     RP-232619 RAN2 topic Enhancements for XR
To be Considered Further
• Enhancements for Multi-Modal flows: No Consensus, but still majority support to do something. If a Study on Multi-modality is to be done in RAN WGs, SA2/SA4 support is required, at least for  synchronization / coordination aspects. A number of companies think RAN should not do any work unless SA2 first identifies requirements.
• Measurement Gaps / Scheduling restrictions: Specify enhancements for reducing the impact to capacity and impact to individual UEs with respect to scheduling restrictions for FR1 and FR2 inter-frequency RRM measurements with measurement gaps and FR2 intra-frequency measurements w/o measurement gaps. [RAN1, RAN2, RAN4].
• UTO-UCI: Almost agreeable: support multiple CG config
• CQI/CSI enhancement: Almost agreeable: CQI/CSI link adaption enhancement (FFS exact scope: PDSCH reception based, Traffic related, Soft-HARQ), FFS CBG enh.
• Delay aware / Delay adaptive (remaining time) scheduling: There seems to be support, not clear how important this feature is. Possibly both DL (network impact only) and/or UL (Uu, UE impact)
• PDCP Discard enhancements for PDU set discard enhancements for inter-PDU Set dependencies: Can consider, if SA2 agrees.
• Power saving: DRX and PDCCH skip (excluding power saving for Multi-modal); Further Power Saving Enh, no consensus for now. Some support to add something if there is time available. Such objective need to be specific.
• RAN involved congestion mitigation / rate adaptation: Some support, feasibility dependent on SA
• FEC awareness at AS: Dependent on SA2, SA4. Some support

 

-     RP-232623 RAN3 topic AI/ML for NG-RAN
Potential Justification / Scope
3 parts:
• Rel-18 leftovers (depends on Rel-18 outcome)
- Mobility optimization
- NR-DC
- UE Trajectory prediction
- Energy saving
- Prediction for energy cost
- Continuous MDT
• At least 1 potential new use case/scenario which benefits from inference-based techniques
- Coverage and Capacity Optimization
- Potential Rel-18 use case enhancements (e.g. new scenarios for ES)
- QoE
- Slicing
  --Note: Model training/inference at the DU and/or F1 enhancements must be justified by the use case
• Study: Consider available functionality specified in 5GC (NWDAF, MDAS) in order to  align  AI/ML framework between RAN and CN

 

-     RP-232624 RAN3 topic SON/MDT Enhancements
Objective 1:
• MRO enhancement for R18 mobility mechanisms, Lower layer triggered mobility (LTM), CHO with candidate SCGs, subsequent CPAC [RAN3, RAN2]:
- Specification of the inter-node information exchange, including possible enhancements to interfaces[RAN3];
- Identify and specify necessary UE reporting to enhance the mobility parameter tuning [RAN2]
Potential Objective 2:
• Only SON/MDT enhancements for intra NTN mobility , Network slicing and NW energy saving are for further consideration. For next meeting, details of these aspects (e.g., spec changes, assessment of workload) should be provided by companies for further discussion. Other new features are ruled out…
For NW energy saving, we should avoid duplication with AI for NG-RAN.
Objective 3:
• R18 leftovers, FFS details, which can be decided based on further progress in RAN2/3 [RAN3, RAN2]

 

-     RP-232617 RAN1 topic ISAC & Exploring Study in New spectrum (7-24GHz)
Regarding ISAC, the following way forward seems agreeable:
1. If not already done in SID, a RAN-led study objective to select a small number of ISAC use cases from TR22.837, and to identify appropriate corresponding information needed for point 2 below, i.e. scenarios, frequency ranges and sensing modes.
2. A RAN1-led study objective to define channel modelling details for sensing using 38.901 (if applicable to the selected use cases) as a starting point, and taking into account relevant measurements, including:
a. modelling of sensing targets, including, for example (if needed by the selected use cases), radar cross-section (RCS), mobility and clutter/scattering patterns;
b. spatial consistency.
This objective to start after completion of the first (RAN-led) objective if not already done in SID.
Regarding the other channel modelling aspects, the following way forward seems close to being agreeable, possibly after some minor further refinement:
3. RAN1-led study objectives to:
a. validate using measurements the channel model of TR38.901 for 7-24 GHz, and
b. to adapt/extend as necessary the channel model of 38.901 for at least 7-24 GHz, including at least the following aspects for applicable scenarios:
i. Near-field propagation;
ii. Spatial non-stationarity.
Note that continuity of the channel model in the frequency domain shall be ensured.
Note that mathematical and/or theoretical aspects (if any) may be studied before results of measurement campaigns are available. Study of measurement results is likely to be able to start in Q3 2024.

 

-     RP-232626 RAN1 additional topics
Multi-carrier enhancements
• From moderator point of view, the following topics seem to be a good starting point for further discussion on potential multi-carrier enhancement in Rel-19:
- Enhancements on multi-cell/user scheduling via single DCI
- Single cell with multiple carriers
Coverage enhancements
• From moderator point of view, the following topics seem to be a good starting point for further discussion on potential coverage enhancement in Rel-19:
- Multiple PRACH TX over different beams including beam selection for Msg3
- PUSCH repetition scheduled by DCI 0_0 with C-RNTI
Positioning enhancements
• Both strong support and strong opposition
• Support of NavIC for L1 navigation band should be supported. Support of NavIC is important for the Indian market. Impact is mainly on RAN2 and there is no impact on RAN1. This enhancement should be considered separately from other positioning enhancements.
Sidelink evolution
• Both strong support and strong opposition

 

 

 

-     RP-232616 RAN1 topic LP-WUS/WUR
Direction 1:
• Waveform-option-1: OOK-1 and/or OOK-4, as described in section 7.2.1.1 (A)(D) in TR38.869.
• Waveform-option-3: Harmonized design that accommodates OOK-1/OOK-4 and OFDM waveform, i.e., specified overlayed OFDM sequences over OOK symbol
• For RRC IDLE/INACTIVE, in addition to existing PSS/SSS, LP-SS (, i.e., OOK-1 and/or OOK-4 waveform with/without overlayed OFDM sequences with potential further down selection in WI phase) for LP-WUR that cannot receive existing PSS/SSS, is supported for synchronization and/or RRM for serving cell.
Direction 2:
• Waveform-option-3: Harmonized design that accommodates OOK-1/OOK-4 and OFDM waveform, i.e., specified overlayed OFDM sequences over OOK symbol
• For RRC IDLE/INACTIVE, in addition to existing PSS/SSS, LP-SS (, i.e., OOK-1 and/or OOK-4 waveform with/without overlayed OFDM sequences with potential further down selection in WI phase) for LP-WUR that cannot receive existing PSS/SSS, is supported for synchronization and/or RRM for serving cell.

 

-     RP-232627 RAN2 additional topics
SL relay
• There is support from companies for SL relay especially to cover the public safety applications
• A starting point for an acceptable objective if it is in Rel-19 package:
- Support for multi-hop L2 relaying for U2N
- For further discussion: multi-path enhancements multi indirect paths for a remote UE
• Concerns from multiple companies on the time required for this additional scope
UP enhancements
• Potential work, if it is included in Rel-19 should focus on 5G advanced UP problems that need and are critical to be addressed within Rel-19. No consensus on the actual scope.
UAV
• Large operator support for UAV (NTT Docomo, Reliance Jio, CMCC, KT, LGU plus, DT, Verizon, China Unicom, AT&T) as one of the most important Rel-19 topics (within the items in this offline) from a commercial and mission critical perspective.
• Architectural changes will not be part of the UAV work (i.e. any architectural enhancements can be considered under NTN)
• Starting point of an acceptable objective:
- Mobility enhancements
o Specifying new CHO triggering events
o Studying/specifying LTM enhancements for UAV
- No transmit zone (if SA2 will also do work on this)
- Enhancements for RRC_IDLE/RRC_INACTIVE
Multi-SIM
• There is some operator support for the WI (including CMCC, China Telecom, China Unicom, NTT docomo, Vodafone, Verizon)
• If the WI is part of Rel-19 package, a starting acceptable objective is:
- MUSIM Gap enhancements
- o To be discussed: Same operator/RAN sharing enhancements (NO RAN1 impact) – Check if it is possible with no SA2 impacts
UE aggregation, collaboration, backup
• Further discussions are required to explain the criticality of the problem for Rel-19
MBS
• Supporting companies indicated that from a deployment point of view ECP and SFN is the most important and critical aspect to address for MBS.
• The following operators expressed support: CBN, China Unicom, China Telecom, and Reliance Jio.
• The objective to support extended CP is RAN1 based and should therefore be considered with the RAN1 items.
NCR
• From moderators’ point of view the following potential enhancements seems like a reasonable starting point (if NCR will be part of Rel-19 work):
- Specify signalling and procedures where NCR-MT controlling an NCR-Fwd in a different carrier, band, and/or frequency range [RAN1, RAN2]
- [Discussions still needed] Specify signalling of side control information to assist NCR setting its amplification gain and/or output power in DL/UL [RAN1, RAN2]
With the above objectives this WI would be a RAN1-led WI so should be considered with other RAN1-led additional items.

 

-     RP-232628 RAN3 additional topics
Potential Justification / Scope
• Support for new services (XR, IIoT, AR/MR) (in coordination with SA4)
• QoE support for NPN, NTN, Sidelink, MBS: no new metric, but e.g. defining specific assistance information [RAN3](not from UE)
• Alignment of QoE measurements with radio related measurements (e.g. RRC_IDLE / INACTIVE, DC) [RAN3, RAN2]
• Any Rel-18 leftovers, if any, to be decided based on further progress in Rel-18 [RAN3, RAN2]
• RVQoE enhancements, to be further discussed [RAN3]

 

-     RP-232625 RAN3 topic Additional Topological Enhancements
WAB and Mobile IAB
• Study enhancements for the support of WAB including (RAN3-led, RAN2):
- Study impact of gNB mobility within a stationary RAN and in proximity to other mobile gNBs:
o Identify the issues of dynamic inter-gNB neighbor relations resulting from gNB mobility, e.g., ANR, inter-gNB HO/DC and SON.
o Identify RAN-related issues when collocating a UPF with the gNB for MEC, local services and/or local inter-UE communications.
o Identify necessary inter-gNB- and gNB-to-CN signaling to address these issues.
- Study the signaling enhancements for the authorization of WAB nodes.
- Study signaling enhancements to extend the IAB resource multiplexing framework to WAB, as necessary.
- Study enhancements to QoS support on WAB backhaul, as necessary.
• Study enhancements for the support of single-donor IAB topology, including (RAN2-led, RAN3):
- Study enhancements to the robustness of multi-hop routing within the IAB topology in presence of local IAB-node mobility.
Note: Access link for WAB backhaul can be TN or NTN.
5G Femto
• Study the overall RAN architecture and required functional and procedural impacts for supporting 5G Femto deployments.
• Study how to define the 5G access control mechanism by (re-)using the existing CAG functionality and identify needed enhancements (if any).
• Study how to enable access to local services from the 5G Femto via collocated local UPF.
Note: The study involves a gap analysis of existing 5G functionality with HomeNB functionality.


Company: 3GPP