结合TV约束的穿墙雷达扩展目标成像方法

摘要

在穿过周期性空心墙体的雷达成像中,当成像区域存在扩展目标时,会有数量较多且呈现区域性分布的散射点,从而导致空间的稀疏性较差,如果仍然采用传统稀疏成像方法,往往得不到理想的结果,为此提出一种TV约束下的扩展目标稀疏成像方法.该方法首先将空心墙体等效为三层均匀介质模 型,基于贝叶斯准则,采用“Integrate-out”方法充分利用目标的先验信息实现目标函数的无参数化,最后利用交替循环迭代法进行循环优化.仿真和实验结果表明,该方法不仅可以对扩展目标进行高分辨成像,还可以有效消除图像中的杂波,并且大大减小了计算量.%In the through periodic cinderblock wall radar imaging,when there is an extended target at the back of the wall,the spatial sparsity is not very effective because a lot of point scatterers present regional distribution.If the traditional sparse imaging method is still adopted,the inferior results are often obtained.Therefore,an extended target sparse imaging method with total variation constraints is proposed.First,the cinderblock wall is considered to be equivalent to a three-layer homogeneous model.Then,the parameter-free objective function is achieved through the method of "integrate-out" based on Bayesian criteria to make full use of the prior information of targets.Finally,the alternating cycle method is used to optimize the objective function.Simulation and experiment results show that the proposed method not only achieves high resolution imagery of the extended target,but also eliminates the clutter are effectively.Also,the calculation amount is reduced greatly.