Effects of bearing estimation improvements of non-conventional beamformers on bearings-only tracking

It has been argued in the open literature that significant improvement in towed array spatial resolution is possible through a variety of non-conventional beamforming techniques such as adaptive and synthetic aperture methods. These techniques are particularly attractive for short arrays where the only other alternative is to lengthen the array at great cost. However, it is important to understand the effect of these techniques on the performance of the complete sonar system. The purpose of this paper is to evaluate and assess the relative merits provided by applying a variety of adaptive and synthetic aperture beamforming techniques to towed array sonar data in order to localize and track signals of interest while suppressing strong interferers. The impact and merits of these techniques will be contrasted with the localization and tracking performance obtained using the conventional beamformer.