Abstract: A new algorithm aiming at improving the estimation accuracy of direction of arrival (DOA) based on uniform circular array (UCA) has been proposed in this paper. Compared with other algorithms, the new proposed one can make the most of the useful information hiding in the received signal by shifting virtually in two vertical direction. Firstly, it shifts the mathematical mode of array received signals at the z axis and x axis respectively with the method of mode excitation. And then, two new full rank Toeplitz matrices relating to the information of DOA estimation have been reconstructed so the purpose of decorrelation has been achieved. Through the different properties of rotation factor at z axis and x axis successively, the researchers obtain the estimation of pitch angle and then the estimation of azimuth angle. Result analysis of simulation shows the validity of the DOA estimation of coherent signal as well as the strong coherence and low SNR incoming signals.

Key words: uniform circular array (UCA); direction of arrival (DOA) estimation; Toeplitz matrix