Staggered SAR: Recent Advances and Design Trade-Offs

Staggered synthetic aperture radar (SAR) is an established concept for high-resolution wide-swath SAR imaging based on multiple elevation beams and continuous variation of the pulse repetition interval (PRI) that is the baseline acquisition mode for the Tandem-L mission proposal and an attractive solution for the NISAR mission and further future SAR missions for frequent global monitoring. Significant developments in the staggered SAR theory have been recently made concerning the characterization of nadir echo and its suppression through processing, the understanding of the advantages of uncorrelated ambiguities for interferometry, the reduction of the data volume to be downlinked, and the simultaneous operation in single-/dual- and quad-pol mode. This paper reviews these advances and discusses some design trade-offs.