Effect of target height on space-surface BSAR imaging

For the Space-Surface Bi-static Synthetic Aperture Radar(SS-BSAR), the transmitter and receiver move in different velocities, and the transmitter-to-target range is disproportional to the receiver-to-target range. Due to this asymmetry construction, the targets with different heights cannot always be focused in the same focal plane. In the paper, the impact of target height on the conventional image formation algorithms is detailedly analyzed, and the variation range of target height that can be focused is deduced. The simulations validate the analysis results. Finally, we suggest that the BPA combined with the DEM of the target terrain should be a method to focus the 3-D scene for the SS-BSAR, if the height variation of the target is not in the range around the focal plane.