Alternative approach to passive sonar

Abstract

An alternative approach to spatial processing for passive sonar is proposed and discussed. It is

considered to offer better performance than conventional and high-resolution beamforming. In

particular, the approach makes it possible to construct a broadband beamformer which outperforms

high-resolution techniques: it provides better resolution, is sidelobe-free, and allows the detection of rather weak sound sources. The approach is based on the analysis of the statistical properties of the different sound sources of interest and allows controlled extraction of the information of interest. It is

also possible with this approach to construct multibeam LOFAR plots which display more than one

beam simultaneously without loss of further information. Since the proposed approach abandons the

estimation of the cross-spectral matrix, it has no greater requirement vis-a-vis the stationarity of the signals than the conventional approach has.