Decreasing high resolution method sensitivity by conventional beamformer preprocessing

In the recent years, the resolving capability of passive array processing has been greatly improved by the so-called high resolution methods. They are based on a more complete modeling of the medium-than previous array processing like adaptive antenna. Their resolving power is basically limited by discrepancies between the model and the actual medium. In this paper, we show by simulation results that the sensitivity can be reduced by implementing high resolution methods at the outputs of conventional secondary beams spanning a limited angular sector. Moreover, this technique reduce the computation load. Results at sea are also presented.