Mainlobe Interference Suppression Method Based on Blocking Matrix Preprocessing with Low Sidelobe Constraint

Adaptive beamforming is widely used in phased array radar for interference and noise suppression. However, when mainlobe interference exists, mainlobe distortion, peak offset and sidelobe level rise will occur, which seriously deteriorate the performance of adaptive beamforming. To address this issue, this paper proposes a mainlobe interference suppression method based on blocking matrix preprocessing (BMP) with low sidelobe constraint. In the method, singular value decomposition (SVD) method is firstly utilized to estimate the angle of the mainlobe interference and blocking matrix is constituted to suppress the mainlobe interference. Then, under the restriction of low sidelobe level, a convex optimization problem is solved to further suppress the sidelobe interferences. Numerical simulations are conducted, and the results show the effectiveness and robustness of the method.