Explicit CSI Feedback Design for NR phase II

Massive multiple input multiple output (MIMO) systems are expected to boost the data throughput and reliability in future 5G systems. In order to enable advanced radio concepts in NR phase II, such as multi-TRP transmission, accurate channel state information (CSI) knowledge at gNB side is essential. This paper provides a practical explicit CSI feedback scheme, which exploits time domain channel sparsity. A heuristic greedy algorithm is used to discover the channel support and feed it back to the gNB. Simulation results comparing the proposed approach against recently standardized NR phase I Type II CSI feedback, shows an improved performance for the proposed design.