Broadband beamforming using fan filter structures with low number of antenna elements

A broadband and computationally efficient beamformer based on fan filters with a reduced number of antenna elements is proposed. The basic idea is the design of two-dimensional filters by application of a transformation to a one-dimensional low-pass filter that has only one adjustable parameter. The modified frequency response of the fan filter makes it possible to use a lesser number of taps and antenna elements. In the partially adaptive interference canceller scheme, interference in the main lobe as well as the side lobe of the directional pattern are suppressed effectively. The adjustment of the adaptive parameters is done by an LMS algorithm and computer simulations are performed to demonstrate the results