Abstract: To derive clutter cancellation, high-resolution angle estimation and wide-area surveillance, space-based radar (SBR) uses a signal processing system of 3-channel DPCA/monopulse. The radar's motion and earth rotation generate a Doppler frequency component in the clutter return form any point on the earth — range walking. We discuss range walking based on the SBR-earth geometry, and show that range walking together with range foldover significantly degrade the clutter suppression performance of the DPCA algorithms. Effects of range walking are eliminated with appropriate inverse compensation during coherent processing interval, and with linear interpolations during non-coherent interval. Effect of range foldover is eliminated using waveform diversity.

Key words: SBR, displaced phase center antenna (DPCA), range walk, waveform diversity