双轴各向异性介质特征参数的测试模型

Measurement Model for the Characteristic Parameters of Biaxial Anisotropic Medium

介质参数测试的关键理论步骤是求解相应的电磁逆问题。本文利用等效传输线法导出了已知双轴各向异性电磁材料复介电常数张量 ε 和复磁导率张量 μ ,计算出反射系数和透射系数 (正问题 )的理论公式后 ,提出了一种新的求解逆问题的理论方法。由介质对正入射 TE、TM波的反射系数与透射系数 ,可用公式直接反演得到ε 和μ 的复分量εx、μy 和εy、μx,然后利用介质对斜入射 TE、TM波的透射系数由大为简化的反演算法迭代求解它们的 z分量 εz 和 μz。计算机模拟实验给出了比较理想的结果。

The inverse problem is of importance in research of characteristic parameters of anisotropic medium. In this paper, the interaction of electromagnetic wave with biaxial slab is introduced in terms of transmission line theory. A new inversion method involved in vector measurement system is given. First,the four complex elements of ε , μ are calculated from the measured reflection and transmission coefficients for normal incidence. Next, ε z and μ z are obtained by inversion algorithn for oblique incidence.The computer simulation gives a satisfactory result.