R1-2600111
discussion
Discussion on 6GR general aspects and frameworks
From Spreadtrum
Summary
This document from Spreadtrum/UNISOC presents 17 proposals and 4 observations addressing 6GR general aspects and frameworks for RAN1#124, covering duplexing types, maximum bandwidth, frame structure, spectrum utilization, scalability, coverage, and TN/NTN integration.
Position
Spreadtrum proposes studying SBFD symbol as a new native symbol type in 6GR frame structure while opposing gNB dynamic SBFD, UE SBFD, and gNB full duplex in Release day1. They require separate discussion of NW-side and UE-side maximum CBW, and separate DL versus UL max CBW at UE side, supporting only Option 2 (dual 200MHz RF + single 400MHz BB) or Option 3 (dual 200MHz RF + dual 200MHz BB) for UE to achieve 400MHz around 7GHz. They propose studying Single Cell Multi-Carrier (SCMC) mechanism for non-contiguous intra-band carriers and DL/UL decoupling, while identifying NTN techniques applicable to TN in day1. They adopt 20MHz as the smallest maximum supported UE bandwidth for low-tier devices, closing high-level scalable design discussions, and require bottleneck channel identification across all RRC states to avoid piecemeal coverage enhancements.
Key proposals
- Proposal 1 (Sec Duplexing type): Not support of gNB dynamic SBFD, UE SBFD and gNB FD in 6GR day1.
- Proposal 2 (Sec Duplexing type): Support at least DL, UL and Flexible symbol/slot types; Study SBFD symbol as a new symbol type; Study Reserved symbols/slots type.
- Proposal 4 (Sec Maximum bandwidth): To enable UE to support 400MHz bandwidth when a network supports 400 MHz Channel Bandwidth (CBW) around 7GHz from UE side, only option2 or option 3 can be optionally supported.
- Proposal 5 (Sec Maximum bandwidth): NW and UE max CBW should be separately discussed, and downlink & uplink max.CBW at UE side should also be separately discussed.
- Proposal 9 (Sec Frame structure): Support of cell specific RRC configuration for 6GR frame structure.
- Proposal 11 (Sec Frame structure): Support a universal harmonized frame structure that can cover all 6GR scenarios, e.g., sensing, NTN, eMBB, Massive Communication (IoT), etc.
- Proposal 13 (Sec Spectrum utilization and aggregation): For efficient and flexible spectrum utilization and operations, study NR MC/CA mechanism, SCMC mechanism at least for non-contiguous carriers within a same band, data scheduling framework across multiple carriers within a cell, DL and UL decoupling, fast carrier activation, UEs with different BW capability served by same base station in same spectrum, and flexible UL Tx switching and DL Rx switching.
- Proposal 14 (Sec Scalability): 20MHz is adopted for 6GR low-tier devices as the smallest maximum supported RF and BB UE bandwidth; RF and BB UE BW are same.
- Proposal 16 (Sec Targeting coverage): To design coverage features for 6GR day1, identify the potential bottleneck DL and UL channels during all RRC states for all device types, use NR coverage features as starting point, and ensure coverage features to meet coverage target are applicable to all device types.
- Proposal 17 (Sec TN&NTN): NTN specific techniques which can be applicable for TN should be identified in 6GR day 1.
- Proposal 6 (Sec Maximum bandwidth): For sub-6GHz, support 100MHz as the max CBW for both downlink and uplink from both NW side and UE side.
- Proposal 8 (Sec Maximum bandwidth): For FR2-1 band (between 24.25GHz - 52.6GHz), support 400MHz as the max CBW from UE side.
- Proposal 15 (Sec Targeting coverage): The link budget template candidates 1 and 2 are used to calculate the metric(s) to compare existing 5G mid-band and 6G deployments in at least around 7 GHz, without further update.
- Proposal 12 (Sec Spectrum utilization and aggregation): Identifies 13 lessons learned from NR spectrum utilization and aggregation framework including CA benefits, slow carrier activation, per-CC HARQ sub-optimality, and late introduction of UL TX switching.