Analysis of Moving Target Acceleration on Azimuth Multichannel SAR Reconstruction

In spaceborne azimuth multichannel synthetic aperture radar (SAR) for high resolution wide swath (HRWS), azimuth multichannel reconstruction is usually required due to azimuth nonuniform sampling. Different from stationary targets, echoes of a moving target should be handled taking account of target’s velocity and acceleration. The impact of acceleration with different velocities on azimuth multichannel reconstruction is analyzed, which results in azimuth defocusing and pairs of false targets in azimuth after azimuth compression. The reason for azimuth defocusing is the changed azimuth modulation rate, while the reason for pairs of false targets is azimuth multichannel imbalance due to the target acceleration, which should be compensated during azimuth multichannel reconstruction. Simulation results of point targets validate the previous analysis.