Shallow Underwater Acoustic Massive MIMO Communications

The potential benefits of massive multiple-input multiple-output (MIMO) make it possible to achieve high-quality underwater acoustic (UWA) communications. Nevertheless, due the wideband nature UWA channels, existing MIMO techniques for radio frequency cannot be directly applied This paper investigates a system in shallow-water environment, deploying large array apertures at both transmitter and receiver. We propose beam-based channel model analyze its properties. Based on this model, we reveal that transmit design rate maximization can performed dimension-reduced space related taps. Then, prove beam-domain transmission is optimal maximize when with unlimited numbers transducers. Furthermore, if number hydrophones also tends infinity, power allocation obtained just by water-filling algorithm corresponding positively correlates taps high signal-to-noise-ratio regime. Moreover, devise low-complexity optimize input covariance matrix general cases. Simulation results illustrate significant performance proposed throughput achieved MIMO.