FUTUREWEI · 10.5.2.3

Futurewei proposes including AI/ML-based DMRS configuration optimization for UL DMRS enhancement, citing experimental NMSE improvements using lower-density DMRS configurations with LS-based preliminary estimation as input to AI/ML models across SNR ranges of 10-30dB. They propose studying per-subcarrier matched-filter based frequency-selective precoding for UL PUSCH that achieves finest precoding granularity while enabling a single wideband channel estimation, claiming the effective channel impulse response collapses to one dominant zero-lag tap. They require supporting SRS as QCL source RS for DL TCI states to enable fast beam acquisition with mixed antenna architectures. They propose reusing and simplifying the 5G NR UL power control framework by consolidating four components (UL transmission, reference transmission, open-loop PC parameters, closed-loop TPC parameters) within a unified TCI framework. They propose eliminating switching-back overhead in UL carrier switching by moving all ongoing transmissions to the target carrier and maintaining a single set of signal/channel configurations across n carriers.

Futurewei proposes adopting the 5G NR MIMO/RS/CSI framework as a starting point for 6G development without fundamental paradigm shifts, while studying targeted enhancements for upper midband (UMB) support including larger Tx/Rx antenna elements with hybrid architectures. They propose studying AI/ML as an integral part of the MIMO framework from day-1, identifying specific use cases to facilitate AI/ML-ready framework design evaluation. For UL transmissions, they propose studying fine-granularity frequency-selective precoding (per-subcarrier matched-filter) that achieves both finest precoding granularity and wideband channel estimation simultaneously, presenting a technical case that 5G NR schemes cannot improve both at the same time. They propose extending the unified TCI framework to support UL signals (SRS) as QCL source RS for DL TCI states, and consolidate UL power control and timing advance mechanisms through flexible component associations via only the unified TCI framework. They propose studying UL carrier switching that maintains transmission continuity by moving all transmissions to the switching-to carrier and eliminating switching-back operations.