The prediction of temporal statistics of directional ambient shipping noise
A technique for predicting the probability density function (PDF) of the ambient-noise power received by a narrow-band system in a modelled shipping and wind noise field is described. The densities of the shipping noise are obtained from a mathematical model for spectral-line components. The importance of the probability of occurrence of combinations of spectralline components in the frequency band of interest is emphasized. It is shown that the uncertainty in receiving a particular combination of lines in the frequency band of interest leads to the definition of the unconditional PDF of the noise. Its predicti on consists of the addition of numerically convolved densities in conjunction with the probability of occurrance of a line combination. The resu l ts show that the shape of the resulting PDF depends on the processing bandwidth and the statistics of the wind/background noise level. Suggestions are made to extend the technique to use it for closer shipping.
SourceIn: Underwater Ambient Noise (SACLANTCEN Conference Proceedings CP-32), Vol. 2, Part 2, 1982, pp. 20-1 - 20-17.