Adaptive antennas offer a practical solution to interference cancellation for radio receivers

Radio receivers are vulnerable to both intentional and unintentional interference. The authors describe the technique of adaptively forming nulls in the antenna radiation pattern to eliminate jamming and interference before these signals enter the receiver. The technique of forming nulls directed towards the interference is complementary to other interference cancellation or ECCM (electronic counter-counter measures) techniques. The term interference cancellation is used in its broadest sense to describe all methods of improving reception of a signal in the presence of interference and not just that of null steering. Potential techniques which are currently used by radio system designers to cancel interference are also discussed