Use of large curvilinear synthetic aperture for 3-D target imaging

Parametric imaging methods for the curvilinear synthetic aperture radar (SAR) are always used the extracted three- dimensional (3-D) target feature (amplitude and 3-D position) to reconstruct the 3-D target image. Their efficient implementations, however, are only suitable for small synthetic aperture case. In this paper, a model is presented for describing the scatterer´s echo received by large synthetic aperture, and based on this model, an efficient parametric method is proposed for imaging the 3-D target. The proposed method removes the coupling between the range and cross- range, which is introduced by range migration. With the decoupled data, the proposed method can replace the high dimensional search with a series of lower dimensional searches, which results in the feature estimates being extracted efficiently. The simulation results show that the method proposed in this paper can achieve the objective of the complex 3-D imaging, and the feature estimates can be reach the corresponding CRBs at low signal-to-noise ratio..