Postbeamformer weak signal extraction with a strong interference colse to the signal´s direction

In the paper, we consider the problem of extracting the weak signal in the presence of a strong interference which is close to the signal´s direction. In our concerned situation, the strong interference is often caused by a cooperative ship, and its direction can be accurately obtained by GPS or Automated Identification System (AIS). A post-beamformer process procedure is proposed to deal with the problem. Beams are densely formed in the adjacent region of the strong interference´s direction. These beam outputs are processed by the beamspace MVDR using the ideal beamspace interference signal model and the post-beamformer interference canceller (PIC) using the beam output in the exact interference´s direction to extract the weak signal information. Some computer simulations were used to analyze the performance of the two methods using the proposed processing procedure.