Single-channel Based on Highlow Orbit Moving Target Detection Technology

When synthetic aperture radar (SAR) imaging is applied to observe ground scene containing a moving target, the imagery of moving target will be typically smeared due to range cell migration and Doppler spectrum broadening caused by the target motions, especially for the accelerating targets within a long observation time. To eliminate these effects, a novel imaging algorithm using cooperative between SAR under high-orbit and low-orbit satellites is proposed. The range migration including range walk and range curvature within the coherent integration period has been corrected via the third order keystone transform. Then, by estimating and compensating the phase errors and the fold factor terms, the target’s resolution is improved and the motion parameters are correctly estimated. The effectiveness of the proposed algorithm is demonstrated by simulations. By combining the generalized keystone method with the subaperture cancellation method, the stationary target clutter can be effectively cancelled, and the moving target can be detected more effectively.