Performance analysis of DOA estimation using dual-polarized antenna arrays

Single- and dual-polarized arrays are used for direction-of-arrival estimation. It has been shown that adding polarization capability to an existing array allows reduction in the source correlation beyond that achieved by only doubling the number of antennas, especially when the sources are closely spaced. Recent work has shown that the joint spatio-polarimetric correlation is an effective measure of the performance dual-polarized arrays. In this paper, we analyze the variance of direction-of-arrival (DOA) estimation of the dual-polarized array. It is pointed out that the performance of dual-polarized arrays is related to both spatial and polarimetric correlation coefficients whereas the performance of single-polarized arrays is only a function of the spatial correlation.