基于块压缩感知的SAR层析成像方法

摘要

基于压缩感知(Compressive Sensing, CS)的SAR层析成像方法(SAR Tomography, TomoSAR)，虽然实现了对目标的3维重构，但对于具有结构特性的目标其重构性能较差。针对这一问题，该文提出了采用块压缩感知(Block Compressive Sensing, BCS)算法，该方法首先在CS方法基础上将具有结构特性的目标信号重构问题转化为BCS问题，然后根据目标结构特性与雷达参数的关系确定块的大小，最后对目标进行块稀疏的l1/l2范数最优化求解。相比基于CS的SAR层析成像方法，该方法更好地利用了目标的稀疏特性和结构特性，其重构精度更高、性能更优。仿真数据和Radarsat-2星载SAR实测数据的试验结果验证了该方法的有效性。%While the use of SAR Tomography (TomoSAR) based on Compressive Sensing (CS) makes it possible to reconstruct the height profile of an observed scene, the performance of the reconstruction decreases for a structural observed scene. To deal with this issue, we propose using TomoSAR based on Block Compressive Sensing (BCS), which changes the reconstruction of the structural observed scene into a BCS problem under the principles of CS. Further, the block size is established by utilizing the relationship between the characteristics of the structural observed scene and the SAR parameters, such that the BCS problem is efficiently solved with a block sparsel1/l2 norm optimization signal model. Compared with existing CS-TomoSAR methods, the proposed BCS-TomoSAR method makes better use of the sparsity and structure information of a structural observed scene, and has higher precision and better reconstruction performance. We used simulations and Radarsat-2 data to verify the effectiveness of this proposed method.