Spreadtrum · 10.5.1.1

Spreadtrum proposes that 6GR initial access design should inherit NR's fundamental procedures, SSB structure (20 PRBs, 4 OFDM symbols), and PSS/SSS/PBCH architecture as the baseline, with a default SSB periodicity of 40ms for initial access to balance UE experience and network energy saving—citing that extending to 80ms yields only 6% additional energy-saving gain under zero load. They require a single unified SSB structure applicable across all deployment scenarios (single/multi-cell, multi-TRP, TN/NTN, all frequency ranges) and oppose introducing different SCS for SSB versus other channels/signals for a given band across all frequency ranges. They propose studying SSB repetition within one SSB period via three options (within burst set, burst set repetition, or combination) and require that at least two SSBs be mappable to one slot of 14 symbols. For on-demand sync signals, they propose further identifying valid scenarios for both network-triggered and UE-triggered mechanisms under standalone (DS#1b, DS#1c) and multi-cell/carrier (DS#2a, DS#2b) deployments, while supporting on-demand SSB for SCell in Day1 and sync signal-less operation for SCell using NR solutions. They require studying AI-based beam prediction for initial access (Sub-use case D) leveraging NR BM-case 1 experience for both SSB spatial prediction and beam refinement prediction, and propose studying enhanced cell DTX/DRX operation in both RRC connected and idle states.

Spreadtrum proposes that NR initial access procedures serve as the baseline for 6GR design with specific evolutionary enhancements. They argue that reducing 6GR sync signal bandwidth by a small margin does not significantly reduce sync raster entries but seriously degrades SSB receiving performance, and present evaluation results showing only 6% additional NES gain when extending SSB periodicity from 40ms to 80ms under zero load. They require same SCS between 6GR PSS/SSS and other channels/signals (except PRACH) for a given band across all frequency ranges, opposing different SCS for SSB versus other channels in FR2-1. They propose studying beam prediction for initial access (Sub-use case D) leveraging AI/ML experience from NR BM-Case 1 for both SSB spatial prediction (Set B subset of Set A) and beam refinement prediction (Set B different from Set A). They support introducing cell DTX/DRX operation in idle state and on-demand sync signals for both single-cell and multi-cell deployments, with NR SSB-less solutions as starting points for sync signal-less operation.