使用液晶設計高頻開關元件

Design for SPST Switch Using Liquid Crystals

張碩耘(Shuo-Yun Zhang)

指導教授 ： 李士修

國立臺北科技大學/電資學院/電腦與通訊研究所/碩士(2010年)

https://doi.org/10.6841/NTUT.2010.00209

摘要

本論文提出使用液晶材料結合微帶線饋入空腔耦合器的技術設計高頻開關元件。微帶線藉由空腔經槽孔耦合至不同層微帶線的結構，如將空腔的內部填滿液晶材料，其液晶材料可以藉由電壓的改變使液晶材料的極化方向跟著變化，而極化方向的變化可以使介電常數發生改變，進而改變微帶線間的耦合效率，如此達到開關的效果。
為了觀察液晶材料介電常數隨電壓變化的情形，本論文同時也設計兩種TE與TM模態的空腔共振器，且將液晶材料置入於空腔內，同時加入電壓來產生電場，如此驗證液晶的極化方向與介電常數的準確性。文中將針對液晶材料做分析與推導，探討出 、導電率、介電常數實部和虛部與Q值等高頻特性，並利用模擬軟體探討理論的正確性，最後以實驗加以驗證。

關鍵字

液晶 ； 開關 ； 空腔耦合器

並列摘要

This thesis presents using liquid crystals material combination of microstrip fed into the cavity coupler technology design for high-frequency switch components. Microstrip line by the cavity through slots coupled to different layers of the microstrip line structure, if the internal cavity filled with liquid crystals material, the liquid crystals material can be made by changing the voltage of liquid crystals polarization along the direction of change, and change the polarization direction can change the dielectric constant, thus changing the coupled efficiency between the microstrip lines, so to achieve switch effects.
In order to observe the liquid crystals material changes in dielectric constant with voltage situation, this thesis also design two types TE and TM mode cavity resonators, and the liquid crystals material into the cavity, while adding voltage to generate the electric field, so verify the polarization direction of liquid crystals and dielectric constant accuracy. In this thesis analysis for the liquid crystals material of the , conductivity, dielectric constant real and imaginary parts and Q factor etc. high-frequency characteristics, using the simulation software of the theory is correct, and finally verified by experiment.

並列關鍵字

Liquid crystals ； switch ； Cavity coupler.

參考文獻

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