An Efficient Method for Analysis of EM Scattering from Objects Straddling the Interface of a Half-Space

作者：Qi, Xin^*; Nie, Zaiping; Que, Xiaofeng; Wang, Yue; Yang, Yuan

来源：IEEE Geoscience and Remote Sensing Letters, 2016, 13(12): 2014-2018.

DOI：10.1109/LGRS.2016.2621134

• Green's function
• half-space
• high-contrast lossy dielectrics
• multilevel fast multiple algorithm (MLFMA)
• scattering
• straddling the interface

An efficient method for the analysis of electromagnetic scattering from 3-D objects straddling the interface of a half-space has been presented in this letter. By truncating the interface, the analysis of scattering from an object within a half-space can be cast into that of a composite (high contrast) dielectric object in the free space. The conventional half-space Green's function involves a Sommerfeld integral that is extremely time-consuming to evaluate, especially when objects get close to or straddle the interface. In this letter, the Green's function of free space has been used to totally avoid the numerical evaluation of Sommerfeld integral. Moreover, fast algorithms, such as the multilevel fast multiple algorithm, can be incorporated easily without any restrictions, effectively compensating the cost due to the introduction of additional unknowns by the truncation. The factors affecting the accuracy and computational cost, such as the truncation radius and the angle of incident wave, have been investigated carefully through an example of a partially buried PEC sphere. A criterion for the truncation radius has been presented based on the coupling mechanism between the scatterer and the interface. Furthermore, the far-field response of the target in a half-space background should be expressed as a differential radar cross section. However, the high contrast problem of air/sea or air/ground requires efficient evaluations, and an integral formulation for modeling high-contrast dielectric objects has been employed to further expedite the computation. Numerical results have been presented to demonstrate the effectiveness and accuracy of the new method.

• 出版日期2016-12
• 单位电子科技大学