Multi-pass stepped frequency imaging of geosynchronous SAR

Geosynchronous orbit synthetic aperture radar (GEO SAR) has a good application prospect for its short repeat period and a wider swath compared to current operating SAR. However, the large orbit height and swath demand high power and data rate. In this paper, a novel imaging mode of multi-pass stepped frequency (MPSF) is proposed based on the particularity of GEO SAR. By observing the same scenario with stepped frequency chirp signals multiple times and composing the coarse resolution images, high resolution images are obtained. Meanwhile, date rate and power budget are significantly lowered. Simulation results indicate the effectiveness of MPSF SAR imaging.