本論文中提出了一種八模態共振器(Eight-mode Resonator)與步階式阻抗共振器(Stepped Impedance Resonator, SIR)的結合方式，以及使用了開迴路共振器(Open loop Resonator)與步階式阻抗來做結合，利用上述兩者架構分別設計出五頻以及六頻的帶通濾波器。
為了因應於多頻段應用的需求，本論文設計了兩種不同架構的多頻帶通濾波器。首先在第一個電路中，為了減少電路面積，使用了一個八模態共振器來產生三個通帶，希望能用較少的共振器數目來產生較多的通帶，並且使用了具有縮小電路面積特性的步階式阻抗共振器，其中包含了二分之一與四分之一波長的共振器架構，最後將八模態共振器和與步階式阻抗共振器結合成一五頻帶通濾波器。
然而在第二個電路中，使用了一個開迴路共振器當作核心架構，將其與另外四組共振器組合成六頻帶通濾波器，此類架構具有相當高的設計自由度，並且能在有限的電路面積中增加最多的通帶。最後在本論文中也提出了其模擬與實作的對照來驗證設計方法是有效的。

A kind of combination of eight-mode resonator and stepped-impedance resonators is proposed in this thesis, and it may also combine an open loop resonator with stepped-impedance resonators as the second proposed circuit. In addition, one can use these combined structures to design quint-band and sext-band bandpass filters, respectively.
For the requirement of multi-band applications, two different structures of multi-band bandpass filter are investigated. Base on the structure of first proposed circuit, one can use an eight-mode resonator to create three bands, and use half-wavelength/quarter-wavelength stepped-impedance resonators to design another two bands. At last, one can combine the eight-mode resonator and stepped-impedance resonators into a quint-band bandpass filter.
Base on the second proposed circuit’s design theory, one can redesign a sext-band bandpass filter by adding four resonator pairs to put in an open loop resonator. Such structure not only increases the freedom of design, but also creates the most bands in a finite circuit size. Eventually, comparisons of experimental and simulated results are presented to verify the theoretical predictions.

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