Frequency selective broadband beamforming using 2D digital filters

In this paper, using the analogy with digital filter design approaches, we will propose a frequency selective broadband beamformer which enables us not only to determine the angle of the main lobe of the directional beam pattern, but also choose the desired frequency band which should be cancelled or enhanced according to the characteristics of the incoming signal. Both characteristics of the beamformer are specified simultaneously in a simple but efficient algorithm. The basic idea is the transformation of the beamforming problem to a two-dimensional digital filter design problem. These dimensions have a direct correspondence with the frequency band of the beamformer and the angle of the main lobe. The broadband characteristics of the passband is achieved by using an appropriate section of the two-dimensional frequency response. The accuracy and precision of the proposed method is justified by computer simulations.