For missile-borne forward-looking SAR in curve trajectory, time-variant motion errors are ignored, leading to degradations in imaging result. This paper proposes a missile-borne forward-looking SAR algorithm based on motion compensation to solve the above problem. The acceleration is divided into forward-looking acceleration and cross-track acceleration, the second phase error and cubic phase error caused by these two accelerations are analyzed in detail. For the cross-track acceleration component, it can be divided into the acceleration vertical to the imaging plane and the one in imaging plane further. Via such dividing, the phase errors caused by acceleration are compensated by using vectorial methods. Moreover, for range migration, it is compensated through Nonlinear Chirp Scaling (NCS) approach based on the accurate 2-D spectrum acquired by the Method of Series Reversion (MSR). The simulated results are given to illustrate the validity of the proposed algorithm.
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