A Gerschgorin radii based source number detection: Analysis and simulations

In this paper, we first analyze the resolution performance of the Gerschgorin radii based source number estimator (GDE, Gerschgorin Disk Estimator) proposed in [1] for independent closely-spaced plane waves. Based upon this analysis, we verify the resolution threshold of the Gerschgorin radii based method for two sources. New close-form expressions of the Gerschgorin radii are formulated and examined. For improvement of detection performance, we then further propose a enhanced GDE method (EGDE). Examples and comparisons with methods based on Gerschgorin radii and weighted Gerschgorin radii, as well as conventional methods are included. Finally, multi-source and/or closely spaced source problems are discussed.