Unitary Approximate Message Passing Detection Method for OTFS Underwater Acoustic Communication System

Orthogonal time frequency space (OTFS) modulation has recently been recognized as a promising modulation scheme for high-mobility communications systems. It can achieve a significant error performance advantages over OFDM in time-varying channels. In this paper, we apply the OTFS modulation for mobile underwater acoustic (UWA) communication. To achieve better performance than AMP,MP detector for OTFS, the unitary approximate message passing (UAMP) based detector is used due to its robustness, low complexity and superior performance. In this work, we firstly apply UAMP-based derector for OTFS to underwater acoustic communication to verify its feasibility. Compared with AMP, MP detector, simulation results show that exhibits better BER performance. Secondly, A lake experiment was conducted in Danjiangkou Lake, Henan, China in July 2022 to vertify the proposed OTFS UWA communicaion schemems. Experiment results show that UAMP detector can achieve a good peorformance at the moving speed of 2 ~4 knots.