DOA Estimation in Solving Mixed Non-Circular and Circular Incident Signals Based on the Circular Array

Non-circular properties of non-circular signals can be used to improve the performance of the direction-of-arrival (DOA) estimation. However, most ready-made algorithms are not applicable to the general case in which both non-circular and circular signals exist. In this paper, we present a novel DOA estimation algorithm for mixed signals, namely MS-MUSIC (Mixed Signals-Multiple Signals Classification), which can deal with the two kinds of signals simultaneously. And on this basis, we derive the Cramer-Rao Lower Bound (CRLB) of the azimuth and elevation estimation. The effectiveness of the algorithm is confirmed by the simulation results. Meanwhile, it acquires higher accuracy than the traditional algorithms.