R1-2508562
discussion
Feature Lead summary #1 on 6G waveform
From Nokia
Summary
This document is the Feature Lead summary (R1-2508562) for 6G waveform in 3GPP RAN1#123, compiling 287 observations and 285 proposals from 44 Tdocs. It covers DL/UL PAPR reduction, other waveforms, and UL multi-layer DFT-s-OFDM, proposing evaluation methodologies, deprioritizing DL DFT-s-OFDM, and serving as a discussion platform for moderator-led questions across offline and online sessions.
Position
Nokia, as moderator, proposes deprioritizing DL DFT-s-OFDM study for PDCCH/PDSCH/PBCH communication while redirecting NTN-related DFT-s-OFDM discussion to an on-line session. They require UL PAPR reduction evaluation to proceed without a single agreed PA model, instructing companies to report their model until RAN4 guidance arrives. For evaluation metrics, they propose net gain at 10% or 1% BLER assuming similar spectral efficiency and bandwidth, and list RAN4 metrics (ACLR, EVM, IBE, SEM), CM characteristic, and receiver complexity as considerations. For UL multi-layer DFT-s-OFDM, they propose separate net gain definitions for power-limited and non-power-limited UEs, and specify 5G NR UL MIMO codebooks with CP-OFDM for all layers and DFT-s-OFDM for single layer as the reference comparison, with fully coherent UE capability and optional Rel-18 DWS disablement.
Key proposals
- Observation 1 (Sec 9): Deprioritize discussion on DL DFT-s-OFDM for PDCCH/PDSCH/PBCH communication
- Observation 3 (Sec 9): For UL PAPR reduction, RAN1 doesn’t select a single PA model for calibration. Companies are to report the model used in their evaluation until further guidance is received from RAN4.
- Observation 5 (Sec 9): Net gain @10% BLER / @1% BLER (depending on the case) assuming similar spectral efficiency and bandwidth for each compared method
- Observation [N] (Sec 8.4): For power limited UEs: Tx power difference [dB] – Rx SINR difference for 10% BLER [dB]
- Observation [N] (Sec 8.4): MPR for multi-layer DFT-s-OFDM to be determined with link level simulations
- Observation [N] (Sec 8.4): Performance benefit to be evaluated using system level simulation
- Observation [N] (Sec 8.4): CP-OFDM for all number of layers & DFT-s-OFDM for single layer
- Observation [N] (Sec 8.4): Fully coherent UE coherence capability
- Observation 4 (Sec 9): Evaluation metrics for UL PAPR reduction
- Observation 6 (Sec 9): RAN4 metrics to be taken into account: ACLR, EVM, IBE, SEM
- Observation 7 (Sec 9): PAPR reduction and SINR degradation @10% BLER, Net gain including MPR can be evaluated by RAN4
- Observation 8 (Sec 9): Implementation complexity in receiver
- Observation 9 (Sec 9): CM characteristic
- Observation 2 (Sec 9): Discuss on-line the question of DFT-s-OFDM for NTN communication
- Observation [N] (Sec 8.4): 5G NR UL MIMO codebooks, frequency selective precoding