A robust and efficient digital FM underwater acoustic voice communication system based on SNR estimation

Abstract

Considering the poor performance of the traditional underwater acoustic voice-communication system that adopts single-sideband (SSB) modulation, we proposed an underwater acoustic voice-communication system adopting frequency modulation (FM). The proposed system achieves digital FM modulation and digital FM demodulation through software radio, which will improve the communication performance meanwhile maintaining a low complexity of the system. To accurately estimate the state of underwater acoustic channels, we improved an estimation algorithm to estimate signal-to-noise ratio (SNR) of the received signal. We also proposed a new FM demodulation algorithm to increase the demodulation efficiency.