Impacts of velocity deviation on spaceborne high-resolution DPCA SAR

Synthetic aperture radar (SAR) based on displaced phase center azimuth multi-beam (DPCA) allows for high-resolution wide-swath imaging, which can overcome the inherent limitation of conventional single-aperture SAR. However, to obtain a uniform sampling distribution in the azimuth direction, the system parameters must fulfill a stringent requirement. Velocity or pulse repetition frequency (PRF) deviation will result in a nonuniform sampling in the azimuth direction. To resolve this problem, multichannel reconstruction algorithms are often employed. In this paper, the periodic nonuniform sampling in the azimuth direction caused by velocity deviation is investigated and the impacts on imaging performance of spaceborne DPCA SAR are analyzed. Simulation examples and simulation results are also provided.