A Sample Correlation Method for Source Number Detection ∗

In this paper, the effective uses of Gerschgorin radii of the similar transformed covariance matrix for source number estimation are introduced. A heuristic approach is used for developing the detection criteria. The heuristic approach applying the visual Gerschgorin disk method (VGD), developed from the projection concept, overcomes the problems in cases of small data samples, an unknown noise model, and data dependency. Furthermore, Gerschgorin disks can be formed into two distinct, non-overlapping collections; one for signals and the other for noises. The number of sources can be visually determined by counting the number of Gerschgorin disks for signals. The proposed method is based on the sample correlation coefficient to normalize the signal Gerschgorin radii for source number detection. The performance of VGD shows improved detection capabilities over Gerschgorin Disk Estimator (GDE) in Gaussian white noise process and was used successfully in measured experimental data. key words: Gerschgorin radii, similar transformation, trans-