基于等效电流源的分层媒质目标反演研究

Investigation on the reconstruction of objects buried in layered media based on the equivalent current source

针对分层媒质目标反演问题,提出了一种基于等效电流源的目标重建方法.该方法首先利用散射数据重建辐射电流源,然后将等效电流源的求解转化为最优化问题来处理,通过共轭梯度方法搜索得到全局最优解,进而实现对目标的反演,该方法充分挖掘了散射数据所包含的信息,缩小了解的搜索空间维度,具有求解效率高的优点.深入研究了频率、采样间隔、采样长度、噪声水平以及背景估计对反演结果的影响,并对上述结果做了理论分析.仿真结果表明,该方法能够较好地实现分层媒质目标的反演,可以应用于穿墙成像、地质勘探等领域.

In this paper, a new algorithm based on the equivalent current source is proposed to reconstruct the objects buried in layered media. In this method the radiating current source from the scattering data is first reconstructed and the reconstruction of equivalent current source and objects are then achieved efficiently by solving an optimization problem in a lower dimensional linear space using the conjugate gradient method. The effects of the frequency of incident wave, sampling interval, length of measurement line level of noise, and the estimation of background on the reconstructed results are studied and analyzed in detail. Numerical results show that the proposed method has a high ability to reconstruct the objects buried in layered media. Therefore, the method can be used to solve the problems in the areas of through-the-wall imaging and geophysical exploration and so on.