Direct Position Determination of Coherent Signals under Direction-Dependent Mutual Coupling

The direct position determination (DPD) approach confronts with many difficulties when determining the position of coherent signals in the presence of direction-dependent mutual coupling (DDMC). In this paper, to restore the rank of data covariance matrix, we extend enhanced spatial smoothing techniques. Then, we extract the middle subarray by using the banded symmetric Toeplitz structure of the mutual coupling matrix of uniform linear array to avoid the effect of DDMC. Finally, according to the orthogonality between the steering vector and the noise subspace, the spatial spectrum function can be derived to locate multiple coherent sources under DDMC. Simulation results show that our solution can accurately determine the emitter position without a priori information of the DDMC.