Having the imaging ability of the area in front of flight direction, forward-looking synthetic aperture radar (SAR) has become a hot topic in areas of SAR research. Nevertheless, constrained by limited azimuth aperture length,the imaging of forward-looking SAR suffers from poor azimuth resolution. Aiming at this problem, an enhanced forward-looking SAR imaging algorithm is proposed in this paper. This algorithm takes both super-resolving ability and computational burden into account. Firstly, an imaging framework is proposed to decrease the computational burden. Secondly, an iterative regularization implementation of compressive sensing (CS) is proposed to improve azimuth resolution. Finally, imaging experiments based on simulated data and Ku-band complex valued image data from the MiniSAR system demonstrate the effectiveness of the proposed algorithm.
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