3GPP Plenary Debrief March 2021 - RAN
DEBRIEF OF 3GPP TSG RAN #91e (electronic meeting), 22-26 March 2021 - Hans van der Veen, NEC Laboratories Europe GmbH and Member of the 5G-IA Pre-Standardization Working Group
- 5G-ACIA (5G Alliance for Connected Industry and Automation) simulations. At RAN#89e 5G-ACIA (5G Alliance for Connected Industries and Automation) had asked RAN for simulation of the Communication Service Availability (CSA). The report shows that NR supports achieving close to 100 % of UEs satisfying the requirements for a relatively large number of users for both uncoordinated and coordinated deployments.
Release 16 Updates
Closed Work Items and Study Items (excluding spectrum-related and conformance testing). The following Rel-16 work was completed and the corresponding SIs and WIs closed:
- WI perf.: Enhancements on MIMO for NR.
- WI perf.: NR Radio Resource Management (RRM) enhancement.
- WI perf.: UE Power Saving in NR.
- WI perf.: Add support of NR DL 256QAM for FR2.
- WI perf.: Physical layer enhancements for NR ultra-reliable and low latency case (URLLC).
- WI perf.: NR performance requirement enhancement.
- WI perf.: Even further Mobility enhancement in E-UTRAN
Release 17 Updates
No changes to planning for Rel-17.
Stage 1: frozen December 2019 with exceptions; all remaining Stage 1 work was completed by June 2020.
RAN "Feature Packaging" ("Content definition") achieved December 2019.
Stage 2: freezing target June 2021.
RAN1: freezing target December 2021. RAN2 and RAN3: freezing target March 2022.
Stage 3: freezing target March 2022.
ASN.1 and open APIs: freezing target June 2022. RAN4: freezing target September 2022.
Rel-17 Closed Work Items and Study Items (excluding spectrum-related and conformance testing). The following Rel-17 work was completed and the corresponding SIs and WIs closed:
- SI: Study on NR positioning enhancements.
- SI: Study on support of reduced capability NR devices.
- SI: Study on NR Sidelink relay.
- SI: Study on NR QoE management and optimizations for diverse services.
NR: Sidelink Enhancement scope (Summary: RP-210840): Enhancements other than inter-UE coordination will not be pursued.
NR: Dynamic Spectrum Sharing scope (Summary: RP-210883). There is no agreement to start normative work on PDCCH of P(S)Cell/SCell scheduling PDSCH on multiple cells using a single DCI. There is no agreement to stop studying this either.
There will be normative work on Non-Terrestrial Networking-IoT in Rel-17, but no additional time allocation for NTN and NTN IoT. A detailed scoping exercise (NTN NR WID revision, NTN IoT WI approval) will be undertaken at RAN#92e (June).
An objective was added to specify configuration of SRB1 and SRB2 for small data transmission in RRC_INACTIVE state by reusing the framework for DRBs (this addition was for the purpose of transmitting positioning information in RRC_INACTIVE).
The objective "Evaluate techniques to cope with CRS interference in scenarios with overlapping spectrum for LTE and NR." was added to the scope. This is related to interference reduction in Dynamic Spectrum Sharing (DSS).
The following set of new high-level objectives was approved, leading to the approved revised WID:
1. Positioning latency improvements.
2. Positioning for UEs in RRC_INACTIVE.
3. On demand Tx/Rx of DL PRS.
4. GNSS positioning integrity.
5. A-GNSS positioning enhancements.
6. Multipath/NLOS mitigation.
The following addition was made to the objective:
Specify mechanism to support DMRS bundling across PUCCH repetitions [RAN1, RAN4].
- When applicable, based on similar mechanism(s) for enabling joint channel estimation for PUSCH.
A 40MHz bandwidth was rejected. 1Rx and 2Rx are supported on condition that there is sufficient access control. An open question is whether Unified Access Control (UAC) can be extended to RedCap devices.
The following additional objective was included in the revised WID: (1) "Specify RF requirements for intra-band UL contiguous CA for UL MIMO". This objective can also apply to UL Tx switching. Consider n41 and n78C as example band combinations.
Approved Work Items and Study Items (excluding spectrum-related and conformance testing)
- RP-210909 WI: NR Uplink Data Compression (UDC)
Keywords: Support UL Data Compression for NR SA scenario; Take LTE UDC mechanism as baseline where appropriate.
- RP-210904 WI: NR Sidelink Relay
Keywords: Enable single-hop, sidelink-based, L2 and L3 based UE-to-Network (U2N) relaying; Common L2/L3 objectives (using LTE solution as baseline): (1) U2N relay discovery and (re)selection; (2) Relay and Remote UE authorization; Objectives specific to L2: (a) Mechanisms for E2E (PC5 and Uu, QoS management); (b) Mechanisms for service continuity (limited to intra-gNB cases); (c) Mechanisms for U2N Adaptation layer design; (d) Control plane procedures for U2N (incl. RRC connection management, system information delivery, paging mechanism and access control for Remote UE).
- RP-210912 WI: Enhancement of RAN slicing for NR
Keywords: (1) Support slice based cell reselection; (2) Support slice based RACH configuration.
- RP-210913 WI: NR QoE management and optimizations for diverse services
Keywords: (1) Support QoE measurement collection in NR standalone mode; (2) Support for QoE measurement collection and reporting continuity in intra-system intra-RAT mobility scenario for signalling based QoE; (3) RAN-visible QoE parameters, with configuration and reporting; (4) Support per-slice QoE measurement; (4) Support alignment of radio-related measurement (i.e. MDT) and QoE measurement.
- RP-210807 WI: Introduction of UE TRP (Total Radiated Power) and TRS (Total Radiated Sensitivity) requirements and test methodologies for FR1 (NR SA and EN-DC)
Keywords: Device types: smartphone, tablet, laptop-embedded equipment (LEE), laptop-mounted equipment (LME); Test scenarios: for smartphone, head/hand phantoms; for other device types, free space (FS) testing; SISO OTA Test methodology enhancement.
- RP-210910 SI: Study on optimizations of pi/2 BPSK uplink power in NR
Keywords: Feasibility of increasing UE uplink power in TDD bands for pi/2 BPSK modulation assuming use of existing UE power classes for FR1 TDD bands n34, n39, n40, n41, n77, n78 and n79.
Some RAN dates are now set:
- RAN: Rel-18 Workshop during week of 28 June - 2 July. (see below for currently available details)
- Stage 1: freezing target December 2021 (TSG#94) (with 80% completion at TSG#93)
- RAN: Rel-18 Work Package (Work Items and Study Items package) target December 2021 (TSG#94)
RAN Rel-18 Workshop, 28 June to 2 July:
The 3GPP TSG-RAN Iworkshop will be electronic and will be structured along a small number of high-level agenda items, such as eMBB evolution, non-eMBB evolution, cross functionalities/new areas. The precise agenda items will depend on the company inputs to RAN#92e. RAN TSG/WG officials will be convenors for the agenda items at the Workshop and will make a baseline document for the discussion by consolidating company inputs submitted to RAN#92e. The RAN#92e meeting itself will be held from 14-18 June and questions for clarification on the company inputs are expected during RAN#92e and the week after.