Robust high-resolution DOA estimation with array pre-calibration

A robust high-resolution technique for DOA estimation in the presence of array imperfections such as sensor position errors and non-uniform sensor gain is presented. When the basis matrix of a sparse DOA estimation framework is derived from an ideal model, array errors cannot be handled which causes performance deterioration. Array pre-calibration via robust steering vector estimation yields an improved overcomplete basis matrix. It alleviates the delicate problem of selecting the regularization parameter of the optimization problem and improves the performance significantly. Thus, closely spaced sources can be resolved in the presence of severe array imperfections, even at low SNRs.