Performance analysis of the data subtraction based robust beamformer

Performance of the sample matrix inversion (SMI) beamformer degrades severely due to the finite sample size effect and the arrival angle mismatch problem. A simple technique to provide robustness to the conventional SMI beamformer is to block the desired signal from the received data before calculating the beamformer´s weight vector, which leads to the data subtraction based SMI (S-SMI) beamformer. In this paper,d we analyse the performance of the S-SMI beamformer in term of its output signal-to-interference-plus-noise ratio (SINR) in the presence of both finite sample size effect and arrival angle mismatch problem.