An Effective DOA Estimation Method of Coherent Signals Based on Reconstruct Virtual Extended Array

The array signal contains many coherent sources due to multipath propagation and co-frequency interference. The traditional spatial smoothing algorithm reduces coherence by sacrificing the effective array aperture, which affects the spatial resolution and the number of sources that can be estimated. To overcome these limitations, this paper proposes a Toeplitz reconstruction method of virtual array extension. This method exploits the non-circular symmetry of the incident signal, extends the array aperture by conjugating the virtual array, and reconstructs the received data of the array by Toeplitz matrix to form the cross-correlation matrix for decoherence. The algorithm utilizes both the cross-correlation and inter-correlation information of the array and mitigates the loss of array aperture. The simulation results demonstrate the validity of the proposed method.