Simulation of non-White and non-Gaussian underwater ambient noise

Noise in the ocean is the result of many contributions. Sources emitting sound in open sea as well as in a coastal area can be placed both in the sea surface and underwater. Excluding the self-noise, the noise impinging a sonar system is called ambient noise and usually is split in two groups: anthropic and natural. In this paper we focus in modeling noise produced by ship transit, which falls in the anthropic category, and noise due to sea surface agitation, that is classified as a natural source. In particular we aspire to simulate the acoustic noise radiated by the machinery of a vessel once the rotational speed of the propeller induces the cavitation effect. Further, we take account of the wind speed action in the sea state and its contribution to the actual underwater ambient noise. An algorithm based on a non-Gaussian approach allows to generate sequence of samples representative of a noise realization having specified kurtosis level and to reproduce the desired source spectrum. The results of the simulation suggest that the surface ship transit can be thought as a major factor in limiting the performance of a underwater acoustic communications systems operating in a coastal shallow waters scenario.