Capon post-processing for wideband target detection

摘要

Low pulse repetition frequency radars aimed at detecting moving targets are faced with the problem of blind velocities, since Doppler ambiguous targets have to compete with clutter and possibly the sidelobes of strong targets. On the other hand, wideband radars have high range resolution, and hence fast moving targets, in contrast to clutter or non-moving targets, are likely to migrate during the coherent processing interval. Moreover, range migration is different between two Doppler ambiguous targets. These properties can be used to remove Doppler ambiguities and detect targets which fall in the clutter or targets sidelobes. In this paper we introduce a method of wideband signal post-processing after coherent integration which allows to achieve significant improvement in sidelobe level. Performance of the proposed algorithm is demonstrated via numerical simulations and real measurements processing giving from 4 dB to 10 dB improvement in sidelobe level depending on signal to noise ratio and target migration.