Robust estimations of DOA and source number with strong and weak signals coexisting simultaneously based on a sparse uniform array

For the problem of the direction-of-arrival (DOA) and source number estimations with coexisting strong and weak signals, a new method for robust estimations of DOA and the number of sources based on an optimized broad band sparse array is proposed. To reduce the impact of the strong signals on the weak ones, an orthogonal projection matrix is constructed by the robust steering vector of the current strongest signal. The proposed method has super-resolution and is robust to array mismatch. The effectiveness of the proposed method is demonstrated by the results of simulations.