Signal Detection and Bearing Estimation for Underwater Sound Sources with Vector Sound Intensity Array

The bearing estimation of underwater low frequency sound sources on a small platform has long been a great challenge to underwater acoustic engineers. A new method of signal detection and bearing estimation for underwater sound sources with vector sound intensity array of limited aperture is proposed. The fundamentals of acoustic signal detection and bearing estimation are presented based on the cross-spectrum p-p sound intensity measurement principle. The processing gain and bearing estimation errors are deduced in detail. Sea trial results show that the bearing of underwater low frequency sound source of tens to hundreds Hz can be estimated on a small platform with an aperture of only 0.4m, which is much superior to the sound pressure processing, since the latter need an array of several meters or more to get the same results.