An Adaptive Antenna for Rejection of Wideband Interference

A modification to the adaptive array under the directional constraint [1] is proposed to improve its performance of rejecting wideband interference. By analogy to the pattern synthesis of an antenna array which produces a flat null in its radiation pattern, an additional quantity that corresponds to the derivative of the pattern is generated and combined with the standard feedback quantity to control the weights of the array. This composite system is tested by computer simulation experiments and the following points are demonstrated in contrast to the conventional, simple system: 1) faster adaptation against wideband interference, 2) remarkable improvement of the signal-to-noise ratio of the output, i. e., very small fluctuation.