R1-2600156
discussion
Other physical layer signals and procedures
From Huawei
Summary
This Huawei/HiSilicon document for the 6G Study Item (FS_6G_Radio) provides 8 proposals and 2 observations covering advanced duplex interference management, remote interference measurement, and scheduling request procedures. The document argues for the adoption and enhancement of 5G NR CLI and RIM features in 6G, while also proposing latency-reducing optimizations for SR/BSR to support critical-latency services like immersive communication.
Position
Huawei proposes studying cross-link interference (CLI) management techniques for advanced duplex modes such as dynamic TDD and SBFD, leveraging and enhancing Rel-16, Rel-18, and Rel-19 features. They support the adoption of UL resource muting (specifically a comb-2 pattern in the frequency domain) and CSI-RS based inter-gNB CLI measurement schemes from 5G NR, while also proposing CSI-RS resource-based UL resource muting to avoid CLI caused by CSI-RS transmissions. For TRP coordination, they present a technical case that native 6G energy saving features (e.g., TRP ON/OFF adaptation based on long-term traffic prediction) can inherently mitigate co-channel CLI, and that 6G's delay-budget-oriented services (as opposed to 5G's latency-optimized UPT) enable packet aggregation, offering more sleep opportunities. They require retaining the physical layer SR for 6G, stating there is insufficient motivation for its removal, and propose studying latency-reduction solutions for the SR/BSR procedure specifically for critical-latency services where the procedure could consume half the transmission occasions within a 10ms PDB.
Key proposals
- Proposal 1 (Sec 2): Cross-link interference management techniques should be studied to achieve the expected performance of advanced duplex modes, e.g., dynamic TDD and SBFD.
- Proposal 2 (Sec 2.1.1): Support UL resource muting based CLI management schemes specified in NR Rel-19 SBFD for 6GR, and further study potential enhancements.
- Proposal 3 (Sec 2.1.2): Support CSI-RS based inter-gNB CLI measurement schemes in 6GR, which was specified in 5G. Further enhancement can be considered in 6GR SI.
- Proposal 4 (Sec 2.2): Study inter-UE interference and/or channel measurement and reporting enhancement and optimization based on the feature specified in Rel-16 and Rel-19.
- Proposal 5 (Sec 2.3): RAN1 should consider the energy saving features and the new 6G service characteristics for CLI coordination between TRPs.
- Proposal 6 (Sec 3): RIM RS and procedures can be considered in 6GR.
- Proposal 7 (Sec 4): Physical layer scheduling request, i.e., SR, should be supported for 6GR.
- Proposal 8 (Sec 4): Solutions to reduce the scheduling latency caused by SR/BSR shall be considered for critical-latency service, e.g., immersive communication.