摘要 本篇論文主要在討論有關介電質量測的技術。我們使用到的量測儀器是網路分析儀(vector network analyzer)，在探討量測技術之前為便利之後量測上的需要，會先對網路分析儀的校準原理加以說明。 而在本篇論文的量測技巧共包含了兩種方法，所針對的對象是非損耗性(lossless)的介質。其中一者是利用NRW (Nicolson-Ross-Weir)法來推算物質的介電係數。而與一般的NRW法較不一樣的是我們還會配合基因演算法(Genetic Algorithms)來修正所推算的結果，如此一來可大大提升量測結果的準確性。 另一則是利用環共振器在其上方介質改變時其共振特性也會跟著改變的原理來推衍待測物之介電係數。最後還會針對待測物一些物理特性改變時對環共振器的影響作一靈敏度的分析。使用上述的兩種介電質量測方法，已可以量測絕大多數無損耗(lossless)介質的介電係數。 Abstract In this paper, we are concerned with techniques for measuring the dielectric constant. We use vector network analyzer in measuring, so we reviewed the calibration of VNA before measuring. In this paper, there are two techniques in measuring. The objects we measure are low loss dielectrics. One of the two techniques is NRW method. We correct the results with genetic algorithms (GA). After using GA we can improve the accuracy of our results. The other of the two techniques, we use the ring resonator. Basically, the dielectric constants are to be inferred from the shift of the resonant frequency and the quality factor of the resonator after placing the resonator in contact with medium. Finally, we make the sensitivity analysis for the results.
