A direct matrix approach to the adaptive nulling problem with multiple look directions utilizing the conjugant gradient method

In adaptive nulling problems, signal cancellation can occur if the direction of arrival (DOA) of the signal of interest (SOI) is unknown and the desired look direction is slightly off the actual DOA. In this case, the signal is considered a jammer and nulled by the adaptive algorithms. Target returns from within a finite extent indicate the presence of a target. This paper investigates the addition of multiple look directions to an adaptive nulling problem in radar. The principles of using multiple look directions are outlined and some illustrative examples are given using a deterministic direct data domain approach.