Estimating ground moving-target parameters for hybrid baseline multi-channel SAR based on migration features in the complex image domain

The hybrid baseline Multi-Channel Synthetic Aperture Radar (MC-SAR) refers to a MC-SAR with both along-track baselines and cross-track baselines. In the hybrid baseline MC-SAR, the phase induced by the target motion couples with the phase induced by terrain, which leads to the difficulty of ground moving target parameters estimation. In this paper, A novel maximum likelihood method based on the migration feature of a moving target in the complex image domain is proposed to estimate the velocity and height of the moving target. Compared with the original maximum likelihood method, the proposed method can decrease the computational load, has a smaller estimated error, and could resolve the ambiguity. The signal model of the terrain clutter and moving target in the hybrid baseline is analysed. A nonlinear antenna configuration is used to decouple the phase induced by moving target and terrain. Finally, some numerical experiments and scene simulation are also provided to demonstrate the estimated performance with different system parameters and the effectiveness of the proposed method.