Joint DOA-polarization estimation based on uniform concentric circular array

A joint estimation method for direction of arrival (DOA) and polarization based on uniform concentric circular array is proposed in this paper. According to the array, manifold vector relationship between electric dipoles and magnetic loops, the least squares solution to the signal polarization parameters, and DOA are given. By maximum likelihood-estimation of signal parameters via rotational invariance techniques method, the space-polarization matrix is obtained from signal subspace by decoupling data covariance matrix. The eigenvalue of space-polarization matrix is used to estimate polarization parameter and the corresponding eigenvector is the steering vector of the whole array. The phase differences between two array elements on inner circle is acquired from the steering vectors of inner circle, which can be used to give rough but unambiguous estimates of DOA; they are used as coarse references to disambiguate the cyclic phase ambiguities in phase differences between two array elements on outer ring circle. Without spectral peak searching and parameter matching, this method has advantages of the small amount of calculation and high precision. Finally, simulation results verify the effectiveness of the algorithm.