本論文提出了一種結合基板合成波導共振器和微帶線共振器的混合結構，並應用於設計具有寬止帶特性的帶通濾波器和雙工器。該結構旨在克服單一結構的限制，通過在電路輸入和輸出端配置基板合成波導共振器來提高頻寬，同時在電路架構中整合微帶線共振器以減少整體電路面積。此設計能夠利用不同類型共振器的架構，錯開其高階模態頻率，實現寬止帶響應。在本文中，帶通濾波器的中心頻率操作於3.5 GHz。設計中對基板合成波導腔體的形狀進行了改造，並與四分之一波長步階阻抗共振器相結合。同時，在基板合成波導腔體中嵌入槽孔，以引入槽孔模態來干擾雜散模態，提升止帶表現。此外，設計中將四分之一波長步階阻抗共振器的尺寸縮小，以減少面積，從而實現整體電路的緊湊化效果。在下一個雙工器電路中，兩通帶之中心頻率分別操作於2 GHz與4 GHz，通過將終端短路步階阻抗共振器整合到半模共振器與四分之一模共振器之間，來操作其基頻與第一高階模態頻率，以實現寬止帶特性。第一級電路的半模共振器，操作的模態為TE101與TE301，其在文中進行了改造，通過改變基板合成波導的金屬通孔邊界，在保留原尺寸之情況下，降低了兩模態頻率，從而減少電路導波波長單位面積。兩個電路的章節末皆有提供量測數據與模擬結果之比較，以驗證設計。

This thesis proposes a hybrid structure combining substrate integrated waveguide (SIW) resonators and microstrip line resonators for designing bandpass filters and diplexers with wide stopband characteristics. The design enhances bandwidth by configuring SIW resonators at the input and output ports, while integrating microstrip line resonators to reduce overall circuit area. This approach exploits different resonator structure to stagger higher-order mode frequencies, achieving wide stopband responses. For the bandpass filter, operating at 3.5 GHz, the design modifies the SIW resonator cavity shape, combines it with a quarter-wavelength stepped impedance resonator, and embeds slots for improved stopband performance. The size of the quarter-wavelength stepped impedance resonator is reduced to achieve circuit compactness. In the diplexer circuit, with center frequencies at 2 GHz and 4 GHz, shorted-end stepped impedance resonators are integrated between half-mode resonators and quarter-mode resonators to control fundamental and high-order mode frequencies for wide stopband characteristics. Modification of the half-mode resonator in the first-order circuit decreases mode frequencies while maintaining original size, reducing the circuit area. Both circuits provide measurement data and simulation results comparison for validation.

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