Source enumeration for high-resolution array processing using improved Gerschgorin radii without eigendecomposition

Accurate detection of sources with low complexity is of considerable interest in practical applications of high-resolution array processing. This paper addresses a new computationally efficient method for source enumeration by using enhanced Gerschgorin radii without eigendecomposition. The proposed method can calculate the Gerschgorin radii in a more efficient manner, in which the additive background noise can be efficiently suppressed and the computational complexity can be considerably reduced. Therefore, the method is more accurate and computationally attractive. Furthermore, the method does not rely on the eigenvalues of a covariance matrix or the signal/noise power, making it robust against deviations from the assumption ofspatially white noise model. Numerical results are presented to demonstrate the performance of the method.