利用缺陷地面共振電路之介質量測技術

Dielectric Measurement Technique using Defected-ground Resonant Circuits

楊安凱(An-kai Yang)

指導教授 ： 丘增杰

國立中央大學/資訊電機學院/電機工程學系/碩士(2011年)

摘要

本論文提出一套新的介質量測技術，以一個雙埠的缺陷地面之共振器當作感測器，主要是設計缺陷地面形狀後，把待測介質樣本置於缺陷地面電路下，使用感測器與待測物之間的地面孔徑耦合效應來達到介質量測的目的。本研究的目的有二個，其一為設計適合的共振電路與新的電路量測校準技術，其二為藉由已知介質樣品的量測，來建立經驗修正模式與反演程序。在電路設計時，透過板材選用來設計出合適的感測器，本次設計的啞鈴形缺陷地面結構感測器，經由介質量測所得透射係數的響應，其等效電路中電容量測介電係數，而電感來量磁導係數的方式，可同時得知低損耗性待測物的介電係數與磁導係數。在U形缺陷地面結構感測器的部分，經由介質量測所得透射係數的響應，使用傳輸零點位移後的頻率反演待測物之介電係數，以及等效電路中電阻來量待測物之正切損耗，可同時得知非磁性待測物的介電係數與正切損耗。本文中使用電磁模擬軟體HFSS完成缺陷地面結構感測器的設計，藉由實作量測待測物之介電係數、磁導係數與正切損耗的結果，驗證設計的正確性。

關鍵字

缺陷地面結構

並列摘要

In this thesis, a new dielectric measurement technique is proposed. The proposed dielectric measurement technique is mainly composed of DGS (defected ground structure). The signal is coupled to the DUT (dielectric under test) from top layer to the bottom layer through the slot aperture on the ground. There are two purposes in research. One of the two purposes is the design of the resonant circuit and the measurement calibration technique. The other of the two purposes is to measure samples, create empirical correction model and inverse algorithm. The dumbbell-shaped DGS sensor is proposed for dielectric and magnetic constants. By measuring the resonant and cut-off frequency with the DUT attached to the sensor, the dielectric and magnetic constants of the DUT can be deduced from the equivalent capacitance and inductance, respectively. The U-shaped DGS sensor is also introduced for measuring the dielectric constant and loss tangent of the DUT. The dielectric constant and loss tangent are to be obtained from the shift of the resonant frequency and the different of the magnitude of the insertion loss, respectively. The simulation results are conducted by using the full-wave simulator, HFSS. The simulated and measured results are in good agreement.

並列關鍵字

defected ground structure

參考文獻

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