Space-Adaptive Ambiguity Suppression in SAR Images

摘要

In this paper we introduce an innovative algorithm to reduce the azimuth ambiguities in Single Look Complex (SLC) SAR images. The technique is based on a bandpass filter that selects that portion of the azimuth spectrum that is less influenced by aliasing, the one that corresponds to the nulls in the replicated azimuth antenna pattern. However, the bandwidth of the filter and the depth of the spectral notch is adapted locally according to (an estimate of) the Signal-to-Ambiguity Noise ratio. The solution is close to a Wiener filter, that provides the most likely reconstruction of the signal, where a strong removal of ambiguities is achieved, at the price of a bandwidth reduction, only where they are present.