R1-2601821
discussion
Discussion on WUS operation in RRC states
From Spreadtrum
Spreadtrum's prior position on
10.6.1.2
at
RAN1#124
· AI-synthesized, paraphrased
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Proposes that 6GR should avoid the duplicated DL-WUS functionalities introduced across NR releases by defining only one DL-WUS type per RRC state. Supports extending the payload size for finer subgrouping granularity and advocates for multi-beam operation via DL WUS occasions composed of multiple monitoring occasions. Proposes using NR mechanisms as a starting point for wake-up delay and DL WUS occasion configuration. Requires that a UE in EE mode can perform serving cell RRM measurements using SSB or LP-SS in a low-power mode under certain signal quality conditions. For connected mode, proposes adopting NR's Option 1-1 and Option 1-2 as the basis for triggering PDCCH monitoring via LP-WUS.
Summary
Spreadtrum provides 2 observations and 7 proposals on DL WUS operation across RRC idle/inactive and connected modes for 6GR, focusing on leveraging NR LP-WUS mechanisms as a baseline while addressing coverage limitations and simplifying connected-mode wake-up signaling.
Position
Spreadtrum proposes that NR LP-WUS mechanisms serve as the starting point for 6GR DL WUS occasion configuration, wake-up delay definition, and connected-mode operation (Options 1-1 and 1-2). They require only one type of DL-WUS in connected mode to avoid duplicated functionalities between DCP and LP-WUS as occurred in NR. They propose serving cell RRM measurement based on 6GR sync signal by EE processing to offload measurements from the main receiver and achieve considerable energy-saving gain, but question the necessity and gain of extending EE processing to neighboring cell RRM measurement, arguing infrequent neighbor measurements via main receiver have negligible energy impact and EE-based neighbor measurement would increase implementation complexity and power consumption. They observe that NR's DL-WUS coverage limitation constrains LP-WUR operation scenarios and note that 6GR's coverage target matching PDCCH may eliminate the need for LP-WUS monitoring state transitions.
Key proposals
- Proposal 1 (Sec DL WUS occasion): DL WUS occasion can to be introduced and one DL WUS occasion consists of multiple DL WUS monitoring occasion.
- Proposal 2 (Sec Wake up delay): For wake up delay, the same mechanism in LP-WUS operation in NR can serve as a starting point.
- Proposal 3 (Sec Configuration of DL WUS occasion): For DL WUS occasion configuration, NR mechanism can be as a starting point.
- Proposal 4 (Sec Measurements and/or synchronization): Serving cell RRM measurement based on 6GR measurement signal (e.g., at least 6GR sync signal) by EE processing can be considered in 6GR.
- Proposal 5 (Sec Measurements and/or synchronization): The necessity and UE energy-saving gain of neighboring cell RRM measurement by EE processing requires further assessment and study.
- Proposal 6 (Sec WUS operation in RRC connected mode): For 6GR, only one type of DL-WUS should be introduced in connected mode.
- Proposal 7 (Sec DL-WUS Procedures to trigger PDCCH monitoring): For LP-WUS operation in connected mode, Option 1-1 and Option 1-2 in NR can be used as a starting point.