R1-2602110
discussion
Remaining Issues on AIML for NR Air Interface
From NEC
Summary
NEC presents four technical proposals addressing remaining issues in AI/ML-based beam management for the NR air interface, specifically focusing on monitoring report behavior, resource availability, and payload formatting. The document aims to resolve ambiguities regarding linked inference report deactivation, PDSCH rate-matching for virtual CSI-RS resources, handling of inapplicable CSI configurations, and PUCCH payload padding.
Position
NEC proposes that for monitoring reports, the UE shall drop the report if the linked inference report is deactivated, ensuring no wrong RS-PAI is reported. They require that P/SP NZP-CSI-RS resources configured for Set A (virtual beams) be available for PDSCH transmission during model inference to prevent unnecessary resource waste from rate-matching. NEC argues that if a CSI-ReportConfig becomes inapplicable due to UE-side model unavailability, the UE shall transmit a CSI report with an invalid value rather than attempting inference. Finally, they support a zero-padding solution for RS-PAI payloads on PUCCH to handle cases where the payload size is 1 or 2 bits, avoiding restrictions on the number of transmission occasions.
Key proposals
- Proposal 1 (Sec 2/TP#1): For a monitoring report, the UE shall drop the report if its linked inference report is deactivated, preventing incorrect RS-PAI reporting.
- Proposal 2 (Sec 2/TP#2): Configured P/SP NZP-CSI-RS resources for Set A (virtual beams) should be available for PDSCH transmission during model inference to avoid resource waste.
- Proposal 3 (Sec 2/TP#3): If a CSI-ReportConfig changes from applicable to inapplicable due to UE model unavailability, the UE shall transmit a CSI report containing an invalid value.
- Proposal 4 (Sec 2/TP#4): Support zero-padding for RS-PAI payloads on PUCCH when the number of information bits is less than 3 (i.e., 1 or 2 bits).