Measurements of dielectric constant are of significant importance. Existing methods, contact or noncontact, require the sample under test (SUT) with a specified dimension. It can be the cross section of a rectangular waveguide or a regular-shaped reference SUT. In this work, a new approach extended from microwave imaging is proposed to remotely measure the dielectric constants of 2-D SUTs with arbitrary cross sections. An algorithm based on scattering integral equations is derived for an efficient parameter retrieval. Experimental measurements based on a time-division bistatic multiantenna system were conducted. It is verified that by deriving an inverse scattering problem-based algorithm, the dielectric constants of such SUTs can be effectively retrieved from the scattering data detected by a measurement setup previously designed for microwave imaging, regardless of the complexity of their cross sections. The proposed approach can be readily applied to various 2-D samples such as dielectric section bars. It can also be conveniently extended to 3-D samples in the future.

中文翻译：

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任意截面样品介电常数的远程测量

介电常数的测量非常重要。现有方法（接触式或非接触式）需要具有指定尺寸的被测样品 (SUT)。它可以是矩形波导或规则形状的参考 SUT 的横截面。在这项工作中，提出了一种从微波成像扩展而来的新方法，用于远程测量具有任意横截面的二维 SUT 的介电常数。一种基于散射积分方程的算法被推导出用于有效的参数检索。进行了基于时分双基地多天线系统的实验测量。验证了通过推导基于逆散射问题的算法，此类 SUT 的介电常数可以从以前为微波成像设计的测量装置检测到的散射数据中有效地恢复，而不管其横截面的复杂性如何。所提出的方法可以很容易地应用于各种二维样品，例如介电截面棒。将来也可以方便地扩展到 3-D 样本。