Institute of Electronic Systems, The Faculty of Electronics and Information Technology, Warsaw University of Technology, Nowowiejska 15/19, 00-665 Warsaw, Poland.
Sensors (Basel). 2023 Jun 7;23(12):5401. doi: 10.3390/s23125401.
We present a novel broadband permittivity characterization method for liquids measured in a semi-open vertically oriented test cell with an uncalibrated vector network analyzer. For this goal, we utilize three scattering matrices measured at different levels of liquid in the cell. With mathematical operations, we remove the effects of systematic measurement errors caused by both the vector network analyzer and a meniscus shaping the top of the liquid samples in such a type of test cell. To the best authors' knowledge, this is the first of such a calibration-independent method dealing with meniscus. We verify its validity by comparing our results with the data available in the literature and with the outcomes of our previously published calibration-dependent meniscus removal method (MR) for propan-2-ol (IPA), a 50% aqueous solution of IPA and distilled water. The new method yields results comparable with the MR method, at least for IPA and the IPA solution, revealing, however some problems when testing high-loss water samples. Nevertheless, it allows one to cut down on expenditures in the system calibration engaging skilled labor and expensive standards.
我们提出了一种新颖的宽带介电常数表征方法，用于在具有未校准矢量网络分析仪的半开放式垂直取向测试池中测量的液体。为此，我们利用在细胞中不同液位测量的三个散射矩阵。通过数学运算，我们消除了矢量网络分析仪和弯月面两者引起的系统测量误差的影响，弯月面形成液体样品在这种类型的测试池的顶部的形状。据作者所知，这是首次针对弯月面的这种与校准无关的方法。我们通过将我们的结果与文献中可用的数据以及我们之前发表的基于校准的弯月面去除方法（MR）的结果进行比较，验证了其有效性，该方法用于异丙醇（IPA）、50%IPA 水溶液和蒸馏水。新方法的结果至少与 MR 方法相当，对于 IPA 和 IPA 溶液，但在测试高损耗水样时会出现一些问题。然而，它允许在系统校准中减少对熟练劳动力和昂贵标准的投入。
