OTFS-Based Downlink Network-Coded Multiple Access With Joint Amplitude-Phase Design

This letter designs an orthogonal time-frequency space (OTFS) enabled network-coded multiple access (NCMA) system for enhancing the throughput in high-mobility scenarios. For the designed system, the impact of power distribution and relative phase offset is theoretically analyzed and the upper-bound symbol error probability is derived into a closed-form expression. To further minimize the upper-bound symbol error probability, a joint amplitude-phase optimization scheme is proposed with using genetic algorithm. Finally, the simulation results reveal that the proposed scheme achieves significant throughput enhancement in high mobility scenarios.