Multiple cluster beamspace and resolution-enhanced ESPRIT

This paper addresses approaches to enhancement of the resolution of one or more clusters of closely spaced emitters. The TLS-ESPRIT algorithm is considered, as applied in beamspace and in element space, in conjunction with resolution enhancement. Beamspace (BS)-ESPRIT employs a matrix beamformer as a preprocessor to map the sensor space into a lower dimensional beamspace. Resolution enhanced (RE)ESPRIT employs a matrix beamformer as a left weighting of the signal subspace eigenvector matrix for enhancing the resolution of ESPRIT. This paper specifically discusses several types of these beamformer matrices, which differ in the way that they treat source clusters other than of interest. Our objective is to clearly define approaches and identify their relative merits, through discussion and illustrative simulation, so as to provide an understanding of how to proceed in designing an ESPRIT algorithm