Research on Real-Time 2-D DOA Estimation Algorithm for Uniform Circular Array

The correlation interferometer algorithm is a commonly used algorithm in the estimation of the direction of arrival (DOA) of a uniform circular array (UCA). However, the real-time performance of the conventional algorithm is poor because of its high computational complexity. In this paper, an improved correlation interferometer algorithm is proposed by reconstructing cost function and narrowing search set. The reconstructed cost function has a steep peak near the actual value of DOA, and the value in other points is 0. A novel search set pre-estimation method is used to narrow search set. By calculating the sine function value of the phase difference of each side baseline, a narrower pre-estimation set can be obtained according to the sign of each sine function value. In the pre-estimation set, the new cost function is used for searching, which can greatly reduce the number of searching times. Experiments show that the proposed algorithm and the conventional algorithm have approximately the same estimation accuracy under different signal-to-noise ratios (SNR), and the processing time of the proposed algorithm is only 12.64% of the conventional algorithm.