R1-2508994
discussion
Views on numerology and frame structure design for 6GR
From HONOR
Summary
HONOR provides 9 proposals and 2 observations on 6G radio numerologies and frame structure design. The document addresses SCS simplification, CP extensions for sensing, FFT size limits, and frame structure enhancements for MRSS, NTN, ISAC, and larger bandwidths.
Position
HONOR requires a single SCS for SSB and initial access per band/sub-FR/carrier type to simplify UE blind detection and accelerate camping. They propose supporting only one SCS per band generally, adding additional SCSs only when the need is well justified. For sensing, they present technical case that NR normal CP durations (e.g., 2.34μs for 30kHz SCS, 1.17μs for 60kHz SCS) cannot meet sensing coverage requirements of 500–1000m, and propose supporting extended CP design within a unified OFDM framework. HONOR proposes confirming 8192 as the maximum UE FFT size, opposing 16K FFT to support 400MHz with 30kHz SCS due to excessive UE complexity. For frame structure, they propose defining a new 'sleeping' symbol/slot type usable for both MRSS and energy saving, deprioritizing DCI-based dynamic frame structure configuration in favor of RRC-based methods, and supporting multiple TDD-pattern combinations with longer patterns than 10ms.
Key proposals
- Proposal 1 (Sec SCS): Supported a single SCS for SSB and initial access per band/sub-FR/carrier type.
- Proposal 3 (Sec CP design): Consider to support extended CP design within a unified framework under sensing sub agenda.
- Proposal 4 (Sec Maximum BW and FFT size): Confirm UE to support 8192 as maximum FFT size.
- Proposal 5 (Sec Migration from 5G to 6G): Consider to define new symbol/slot type, e.g. sleeping, which could be used for MRSS and energy saving.
- Proposal 6 (Sec Support for various services including sensing and NTN services): RAN1 should at least agree to study and may introduce necessary enhancement in 6G frame structure design for NTN and ISAC and detail discussion could be under other AI.
- Proposal 7 (Sec Support larger carrier bandwidth): The design of the 6G frame structure needs to consider flexibility in the frequency domain.
- Proposal 8 (Sec Configuration method): Multiple TDD-pattern combinations and longer pattern than 10ms can be supported in 6GR.
- Proposal 9 (Sec Configuration method): Cell and UE specific RRC configuration for frame structure can be reused for 6G and DCI based configuration should be deprioritized.
- Proposal 2 (Sec SCS): Consider one SCS for one band, and add more SCSs for one band only the need is well justified.
- Observation 1 (Sec CP design): Inherent conflict exists between communication and sensing requirements for CP duration.
- Observation 2 (Sec CP design): The CP duration of NR system may not meet sensing coverage requirements.