On the performance of underwater communication system in noise with Gaussian Mixture statistics

Underwater acoustic (UWA) communication in shallow water areas is often affected by the impulsive components of ambient noise. The noise statistics in such cases does not follow the traditional Gaussian behavior. On the other hand, most communication receivers are designed with Gaussian noise assumption. Performance of such systems may not be optimum in the presence of non-Gaussian noise in a UWA channel, and, so, the scenario demands an investigation. Among the several non-Gaussian noise models proposed in various literature, the Gaussian Mixture (GM) distribution is popular due to its "universal approximation" properties. However, despite its popularity in modeling UWA noise, none has yet reported any analytical analysis of error probability assuming GM noise statistics in the UWA channel, to the best of our knowledge. In this paper, we present a study on the error performance of a UWA communication system considering channel noise to be a mixture of Gaussian components. We derive the analytical expressions of probability of error for BPSK, QPSK and M-PAM constellations. We also simulate a UWA system where the performance of a traditional Gaussian receiver is studied in the presence of GM noise. It has been observed that in the presence of GM noise, the system performance degrades significantly from the usual one expected in a Gaussian noise environment and becomes a function of the mixing coefficients of the GM distribution.