A spatial exploration based blind DOA estimation algorithm for closely spaced sources

In this paper, a spatial extrapolation-based blind DOA estimation method is presented for closely spaced sources. The new method is based on the linear extrapolation of the correlation matrix using AR coefficients, which are first estimated through an initial DOA estimation. Both the initial and final DOA estimations are performed by using the ESPRIT algorithm. Unlike conventional AR coefficient estimation method which estimates AR coefficients on the snap-shot basis, our AR coefficient estimation is carried out in correlation domain once a block of snap-shots, thus significantly reducing the computational complexity of the antenna array. Computer simulations show that the proposed blind DOA estimation method outperforms the conventional method in terms of the mean square-error (MSE) when the angle of separation of DO As is very small.