An efficient NLCS algorithm for maneuvering forward-looking linear array SAR with constant acceleration

Forward-looking linear-array synthetic aperture radar (FLLA-SAR), which can overcome the deficiency of the traditional SAR on forward-looking imaging, continues to gain in significance due to the various applications, such as unmanned aerial vehicle (UAV) reconnaissance. To compensate the space-variant characteristic of along-track frequency modulation (FM) rate caused by the high speed maneuvering UAV, an efficient nonlinear chirp scaling (NLCS) algorithm is proposed in this paper. Based on the analysis of novel geometric configuration and the introduction of NLCS operation, the linear-array UAV SAR can reconstruct the 2-D image of the scout area. Finally, the validation of the proposed algorithm is done by exploiting the simulated data based on 3 × 3 array point targets and an airplane scattering model.