Direction of arrival estimation for GPS signal via Toeplitz approximating the cross-correlation matrix

In Global positioning system (GPS), adaptive beamforming is an effective method for enhancing the desired signal and suppressing interferences simultaneously. The direction-ofarrival (DOA) of the desired signal, however, as a priori information, is required. Due to very lower signal-to-noise ratio for GPS signal, the DOA estimation is a challenge problem. In this paper, a preprocess is presented which Toeplitz approximates the cross-correlation (CC) matrix. The matrix Toeplitz approximation recovers the Toeplitz structure, and the approximated matrix is used to obtain more accuracy estimates via MUSIC method.