本論文以印刷電路板技術實現電感與電容元件，達成小型化且寬頻的微帶線至基板合成波導轉接，分別討論三種高阻抗微帶線至低阻抗基板合成波導的轉接結構以及三種低阻抗微帶線至高阻抗基板合成波導的轉接結構。
關於三種高阻抗微帶線至低阻抗基板合成波導的轉接結構，首先，第一種使用直接轉接的長度為0 mm，在X-band (8.2-12.4 GHz)中，其-20 dB反射係數頻寬只有19.08%。第二種我們使用微帶線開路殘段轉接結構，其-20 dB反射係數頻寬為48.21%，相當寬頻，幾乎涵蓋整個X-band (8.2-12.4 GHz)，轉接電路長度為2.3 mm。第三種我們使用基板合成波導開路殘段的結構做轉接，電路長度可以縮短為1.4 mm，而其-20 dB反射係數頻寬有49.7%，在頻寬表現上也是相當良好，並且輻射量減少1.88%，最後，我們以背對背的結構的方式進行量測，並使用TRL校準去除SMA效應，驗證結果正確性。
關於三種低阻抗微帶線至高阻抗基板合成波導轉接結構，第一種使用直接轉接的長度為0 mm，但是在Ku-band (12.4-18 GHz)中，其-20 dB反射係數頻寬只有23.09%。第二種使用基板合成波導短路殘段之轉接結構，其-20 dB反射係數頻寬有40.9%，頻寬相當寬頻，但轉接電路長度稍長為4.1 mm。第三種使用基板合成波導指叉型電容轉接，其-20 dB反射係數頻寬有37.06%，頻寬相當寬頻，且轉接的電路長度減少為1.7 mm，最後，我們使用背對背結構的方式進行量測，並使用TRL校準去除SMA所造成的接頭效應，驗證模擬結果的正確性。
為了降低板材的損耗，高階的板材是必須的，而板材成本也會跟著提高，小型化的設計能夠直接降低板材的成本，因此，本論文探討了許多種減少電路面積之設計，以提升實務上的價值。

his thesis employs the printed circuit board (PCB) technology to realize the lumped inductance and capacitance elements, accomplishing a compact and broadband microstrip line to substrate-integrated waveguide transition. These transitions include three high-impedance microstrip line to low-impedance substrate-integrated waveguide transitions and three low-impedance microstrip line to high-impedance substrate-integrated waveguide transitions.
Concerning the three high-impedance microstrip line to low-impedance substrate-integrated waveguide transitions, the simplest is the direct microstrip line to substrate-integrated waveguide transition, which has a transition length of 0 mm. However, the -20-dB fractional bandwidth is only 19.08%, which can only cover part of the X-band (8.2-12.4 GHz). To increase the fractional bandwidth, the microstrip line to substrate-integrated waveguide transition using the microstrip line open-circuited stub is proposed. The -20-dB fractional bandwidth is increased to 48.21%, which covers the entire X-band (8.2-12.4 GHz), and the transition length is 2.3 mm. To decrease the transition length, the microstrip line to substrate-integrated waveguide transition using the substrate-integrated waveguide open-circuited stub is proposed. The -20-dB fractional bandwidth is increased to 49.7%, which covers the entire X-band (8.2-12.4 GHz), while the transition length is reduced to 1.4 mm. Also, the radiation loss is solely 1.88%. Back-to-back microstrip line to substrate integrated waveguide transitions are fabricated and measured with the TRL calibration to verify these results. The simulation and measurement results are in reasonable agreement.
Concerning the three low-impedance microstrip line to high-impedance substrate-integrated waveguide transitions, the simplest is the direct microstrip line to substrate-integrated waveguide transition, which has a transition length of 0 mm. However, the -20-dB fractional bandwidth is only 23.09%, which can only cover part of the Ku-band (12.4-18 GHz). To increase the fractional bandwidth, the microstrip line to substrate-integrated waveguide transition using the substrate-integrated waveguide short-circuited stub is proposed. The -20-dB fractional bandwidth is increased to 40.9%, which covers the entire Ku-band (12.4-18 GHz), and the transition length is 4.1 mm. To decrease the transition length, the microstrip line to substrate-integrated waveguide transition using the substrate-integrated waveguide interdigital capacitor is proposed. Although the -20-dB fractional bandwidth is reduced to 37.06%, it still covers the Ku-band (12.4-18 GHz). The transition length is reduced to 1.7 mm. Back-to-back microstrip line to substrate-integrated waveguide transitions are fabricated and measured with the TRL calibration to verify these results. The simulation and measurement results are in reasonable agreement.
Although low-loss advanced substrates are necessary to reduce the transition loss, they are costly. To minimize the cost, the transition length should be miniaturized. Therefore, this thesis proposes several compact and broadband microstrip line to substrate-integrated waveguide transitions to accomplish this goal.

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