Adaptive nulling beamformer for rejection of coherent and noncoherent interferences

An adaptive beamforming method is presented which rejects coherent and noncoherent interferences by using an interference subspace, which is efficiently obtained from a submatrix of the covariance matrix of received signals. The use of the submatrix enables an increase in the effective array aperture size, as compared with the existing correlation-vector-based beamformer (CVB). As a result, the proposed beamformer can provide superior performance than conventional methods such as CVB and the weighted spatial smoothing (WSS).

► We present an adaptive beamformer which efficiently suppresses coherent and noncoherent interferences.
► The proposed beamforming method exploits a submatrix of the covariance matrix of received signals to find an interference subspace.
► The effective array aperture size of the beamformer is increased, which enables it to enhance interference rejection capability and to provide an improvement in SINR.