A new method for adaptive wideband beamforming

Classical angle of arrival (AOA) estimation methods assume incoming signals are either purely narrowband or purely wideband in nature. There are many physical scenarios where this may not be the case. The authors call such scenarios mixed, in that the incoming signals contain a combination of both wideband and narrowband components. They introduce a new method for performing AOA estimation using a wideband adaptive beamsummer in the presence of mixed (narrowband and wideband) signals. The method uses an adaption criterion which is a function of both the mean and variance of the beamsummer output. The method is an extension of a similar narrowband beamsummer method (ICASSP1992 vol.4, p.461-4). Simulation results are presented which compare the performance of the new criterion with the standard narrowband and wideband adaptation criteria. These results show that the new method can perform as well or better than the classical methods in terms of target resolution and angle of arrival estimator variance. >