Underwater Ambient Noise — An Estimation Methodology

摘要

The use of the submarine weapon in the various naval operations has increased significantly in the last decades. Due to their tactical advantages over other vessels, it is necessary to create tools supporting sonar forecasting and enabling underwater acoustics modeling. One of the variables that limit sonars performance is the so-called spectral ambient noise. There is a need to study the way in which it masks or affects the signal coming from the targets to be detected or the signal emitted by the acoustic system itself. In order to assign adequate values to ambient noise levels, existing graphics were analyzed, having in account the meteorological and oceanographic conditions, and the area navigation density; however, those do not include all meteorological and oceanographic conditions. In order to interpolate or extrapolate the existing data, to overcome such limitation, a software was created, with the help of the MATLAB tool, for a least squares data fitting. It is only necessary to introduce the operating frequency of the acoustic system, the wave height or sea state, precipitation level (absent, weak, moderate, strong or very strong) and the navigation density (low, moderate or high). In the end, the program returns the value of spectral ambient noise.