Spaceborne stripmap range sweep SAR: positive terrain tracking by continuous beam scanning in elevation

In this study, an innovative spaceborne stripmap range sweep synthetic aperture radar (SS-RSSAR) is proposed to effectively image tilt ground strips with respect to the satellite orbit. Distinguished from the conventional spaceborne stripmap SAR, the SS-RSSAR implements a region-matched swath coverage by positively tracking the region of interest using a continuous scan-in-elevation beam. Two aspects of the SS-RSSAR, the beam illumination and the spatial sampling, are focused. Specifically, the article presents detailed discussions on why a ‘perpendicular-to-strip’ beam pointing is preferred and how an innovative ‘multi-interval sampling technique’ works to avoid the transmitting blockage caused by the slant range variation of dozens of kilometres. The preliminary simulation results are provided to evaluate the presented approach.