使用空腔耦合之微帶線垂直轉接而設計之超寬頻帶通濾波器

Designs for Ultra Broad-Band Band-Pass Filters Using Microstrip Cavity-Couplers

莊志忠(Chin-Chung Chuang)

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(2008年)

https://doi.org/10.6841/NTUT.2008.00145

摘要

本篇論文主要是敘述採用圓形空腔耦合的微帶線垂直轉接的結構，利用改變耦合槽孔和微帶線開路殘斷的幾何形狀，來達到增加頻寬的目的，再透過串接其他種濾波的技術，在些微影響通帶的介入損失之下，將截止帶延伸至30 GHz，成為一款高選擇性的超寬頻帶通濾波器。第一款步階式阻抗低通濾波器經過適當的改良，可得到寬廣的截止帶，用來衰減通帶以外絕大部分的訊號。第二款為由高Q值慢波共振器而設計之低通濾波器，可有效的衰減靠近通帶旁的雜訊。最後利用在微帶線上形成指叉型結構，進一步衰減其他地方零星的雜訊。
本篇論文是利用以有限元素法為基礎而發展的高頻結構模擬軟體（High Frequency Structure Simulation；HFSS）來進行模擬，主要是根據過去在微帶線垂直轉接結構之精準模擬的經驗，模擬的結果會再以實驗數據加以應證。

關鍵字

垂直轉接 ； 空腔耦合 ； 超寬頻 ； 帶通濾波器 ； 慢波共振器 ； 指叉型

並列摘要

This thesis mainly focuses on the the structure of microstrip vertical transitions of circular cavity-couplers by changing the geometric shapes of slot aperture and microstrip terminated by open-circuited stubs，to achieve the purpose of bandwidth enhancement. By cascading other filter techniques can minimize the pass-band insertion loss and furthermore expand the rejection-band to 30 GHz，which allows this ultra broad-band band-pass filter to become high selectivity. The first model of stepped impedance low-pass filter, under certain modifications, can extend the range of rejection-band to attenuate the unnecessary signals to pass-band while the second model of low-pass filter, constructed of high quality slow-wave resonator, can effectively diminish the noises near the pass-band. Lastly, by using the interdigital from microstrip can further reduce the noises from other places.
This paper uses FEM as a base to develop a stimulation of High Frequency Structure Simulation, which focuses on the past precise simulation experiences of the structure of microstrip vertical transitions, the results of such stimulation is yet to be proven from statistical results.

並列關鍵字

Vertical transitions ； cavity-couplers ； ultra broad-band ； band-pass filter ； slow-wave resonator ； interdigital.

參考文獻

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