DOA estimation of mixed circular and non-circular signals using uniform circular array

In this paper, the main purpose of our algorithm is to solve the two-dimensional estimation problem under the more practical case of circular and non-circular signals coexist. Firstly, taking advantage of non-circularity properties, we extend the received data matrix to augment the maximum number of detectable signals. Secondly, utilizing unitary extended propagator method (UEPM), we obtained a higher estimation accuracy with less computational burden. In addition, we separate the estimation of circular and noncircular signals. And using uniform circular array (UCA), azimuth and elevation angle are estimated at the same time. Simulation results certificate that our proposed method has good performance under low signal to noise ratio (SNR) and small snapshots. Moreover, the 2-D estimation results of our algorithm are accurate and perform better than MUSIC and NCMUSIC methods.