A new computational technique for processing transmission-line measurements to determine dispersive dielectric properties
A new computational technique for processing transmission-line measurements to determine dispersive dielectric properties
复制标题
一种用于处理传输线测量以确定色散介电特性的新计算技术
作者：
B. Oswald;J. Doetsch;K. Roth
随着网络分析仪和时域光谱仪的使用，在宽频率范围内对介电材料性质的精确测量已经有了相当大的进步（科尔和科尔，1941，1942; Fellner-Feldegg，1969;科尔，1975 a，B;科尔等人，1980; Feldman等人，1992; Berberian，1993; Feldman等人，1996; Berberian和King，2002; Huisman等人，2004年）。这些方法的频率范围（1-10 000 MHz）包括探地雷达（GPR）和时域反射（TDR）系统和极性液体和分散粘土的弛豫频率。这些材料中的一些，特别是膨胀粘土（例如，膨润土、蒙脱石），似乎具有离散的弛豫时间而不是被认为是复杂材料特征的连续体（Ishida等人，2000）。在这份说明中，我们测试的解释程序，采用遗传优化算法来模拟色散介电性能的离散弛豫时间的德拜模型。使用网络分析仪测量膨润土（散射系数），我们产生一个德拜模型，这是物理上合理的和自洽的，它满足Kramers-Kronig关系。
Precision measurements of dielectric material properties over a wide frequency range have advanced considerably with the use of network analyzers and time-domain spectrometers (Cole and Cole, 1941, 1942; Fellner-Feldegg, 1969; Cole, 1975a, b; Cole et al., 1980; Feldman et al., 1992; Berberian, 1993; Feldman et al., 1996; Berberian and King, 2002; Huisman et al., 2004). The frequency range of these methods (1–10 000 MHz) encompasses those of ground-penetrating radar (GPR) and time-domain reflectometry (TDR) systems and the relaxation frequencies of polar liquids and dispersive clays. Some of these materials, especially the swelling clays (e.g., bentonite, montmorillonite), appear to have discrete relaxation times rather than the continuum thought to be characteristic of complex materials (Ishida et al., 2000). In this note we test an interpretational procedure that incorporates a genetic optimization algorithm to model dispersive dielectric properties using a Debye model with discrete relaxation times. Using network analyzer measurements of bentonite (scattering coefficients), we produce a Debye model that is physically reasonable and self-consistent, and it satisfies the Kramers-Kronig relationships.