Direction finding for point and dispersed sources: VEC-MUSIC and its performance

A prime objective of array processing is to estimate the location of signal sources. The signals in many applications such as ocean exploration, radar and radio communications could appear to be from either point sources or spatially dispersed ones. Previously, a few methods have been proposed to estimate the DOA of dispersed sources. Among them, VEC-MUSIC [Wu et al. 1994] has the property of jointly estimating the DOA of point and dispersed sources. In this paper, the the unique ability of VEC-MUSIC to distinguish a point source from a dispersed source using different noise subspaces is demonstrated. The asymptotic performance of VEC-MUSIC is also analyzed.