Fast Direction of Arrival Estimation and Identification of Mixed Circular and Non-Circularity Sources

In array signal processing, the cases of mixed circular and non-circular sources are more and more frequently encountered in complex signal situation. By analyzing the subspace property of the mixed circular and non-circular signal sources in detail, an enhanced and fast method for direction of arrival (DOA) estimation and identification of mixed circular and non-circular sources is proposed. Since the proposed method efficiently utilizes the useful non-circularity properties of the mixed circular and non-circular source model, it has better performance of DOA estimation compared with the method only based on homogeneous source model and its performance is closed to the theoretical bound. Simulation results show that by using the proposed method in DOA estimation, the number of mixed signal sources can be larger than the number of array elements.