Analysis of elevation-based distributed SAR imaging concepts

Abstract

This paper discusses the potential of a multi static SAR constellation in elevation to deliver high resolution imaging over wide areas. The reference system consists of several radar satellites distributed in the elevation plane with antennas tailored to the target azimuth resolution and operated over their natural Nyquist frequency, capable providing images over wide swaths. Unlike the case of distributed constellations in azimuth, the suggested approach may help prevent undesired phase jumps within the synthetic aperture, leading to more robust ambiguity rejection capacities. Images of a single element will be contaminated by range ambiguities, which are suppressed on ground by a coherent combination of the data from all elements of the constellations. Within the assumptions of our analysis, we found that a swath extension of a factor of N can be typically achieved by using a constellation of 1.5 · N satellites