A New Path Division Multiple Access for the Massive MIMO-OTFS Networks

This article focuses on a new path division multiple access (PDMA) for both uplink (UL) and downlink (DL) massive multiple-input multiple-output network over high mobility scenario, where the orthogonal time frequency space (OTFS) is adopted. First, 3D UL channel model received signal in angle-delay-Doppler domain are studied. Secondly, 3D-Newtonized matching pursuit algorithm utilized extraction of parameters, including gains, directions arrival, delays, Doppler frequencies, antenna-time-frequency domain. Thirdly, we carefully analyze energy dispersion power leakage channels. Then, along UL, design scheduling to properly assign angle-domain resources at user sides assure that observation regions different users do not overlap cubic area, i.e., After scheduling, can map their respective data scheduled delay-Doppler grids, simultaneously send base station (BS) without inter-user interference same OTFS block. Correspondingly, signals desired grids within resource BS separately collected implement estimation maximal ratio combining-based recovery construct low complexity beamforming scheme achieve free DL communication. Simulation results provided demonstrate validity our proposed unified UL/DL PDMA scheme.