Underwater acoustic communication using Doppler-resilient orthogonal signal division multiplexing

Underwater acoustic (UWA) communication is an ongoing challenge because of the heavy time and frequency spread in the UWA channel. In this paper, we propose Doppler-resilient OSDM (D-OSDM) to provide robust UWA communication under heavy multipath and Doppler spreads by combining the orthogonal signal division multiplexing (OSDM) technique and orthogonal multiple access. We show that D-OSDM idea proposed here can utilize the full energy spread in the frequency domain. We evaluate D-OSDM communication by comparing it to the existing OSDM in a baseband simulation with a reverberation time of almost 60 symbols and a Doppler spread of up to 45 Hz, and this under the same data rate. Although D-OSDM requires a larger bandwidth compared to the existing OSDM, D-OSDM achieves a far better bit-error-rate (BER) performance compared to the existing scheme, under the same data rate. We expect that D-OSDM can become a viable alternative offering a highly reliable communication environment for shallow-water UWA channels.