Multistatic SAR Image Formation for Nonzero Cross Track Baselines

A wide-swath synthetic aperture radar (SAR) image is known to be achievable by merging multistatic aliased data that is collected with an appropriate along track displacement. However, in terms of both flexibility requirements like potentiality of both along track and cross track interferometry and design requirements like orbital safety etc., a cross track baseline is not only demanded but also unavoidable. In this work, two methods are proposed in order to merge SAR data to recover the Doppler spectrum unambiguously for the non zero cross track baseline case. The algorithms are compared and validated by simulating an azimuth invariant multistatic SAR satellite constellation. The results are promising in terms of dealing with long cross track baselines.