本論文使用不對稱漸變探針結合三角形耦合元件，來實現微型且寬頻的微帶線餽入天線。由於使用不對稱漸變探針，微帶線訊號可以直接餽入天線以形成微型的天線。除此之外，這個天線的反射係數小於–10 dB的頻寬涵蓋9.24 ~ 18.14 GHz，可謂相當的寬頻。再者，在這個頻帶內，天線的輻射場形都是全向性的。
為了實現微型且寬頻的微帶線至矩形波導轉接，我們把使用不對稱漸變探針的微帶線天線，直接放入矩形波導中。這個轉接的返回損耗小於15 dB的頻寬涵蓋8~13 GHz，超越X-band (8.2–12.4 GHz)的範圍。並且，在這個頻帶之內，其插入損耗皆小於0.22 dB。和使用漸變共面帶線的轉接以及使用漸變鰭線的轉接比較，這個轉接不但有較寬的15 dB頻寬，並且有較小的尺寸。
為了實現微型且寬頻的矩形波導功率分配器，我們整合三個使用不對稱漸變探針轉接與T型連接器。使用T型連接器結合不對稱漸變探針的矩形波導功率分配器有寬頻的響應。在8.48 ~ 12.04 GHz的頻率範圍內，其輸入埠的反射係數小於–15 dB，並且其輸出埠的傳輸係數約–3.2 dB。
為了將這個功率分配器升級為功率分配與結合器，我們使用威金森功率分配器來取代T型連接器。使用威金森功率分配器結合不對稱漸變探針的矩形波導功率分配與結合器，在X頻帶的範圍內，有低反射係數、等功率輸出且好隔離度的優點。在8.44 GHz ~ 12.6 GHz的頻率範圍內，其輸入埠的反射係數小於–15 dB，並且其輸出埠的反射係數小於–12.6 dB。除此之外，其輸出埠的傳輸係數約–3.3 dB，並且其輸出埠的隔離度小於–17.5 dB。
為了驗證以上所述之設計，我們實際製作了不對稱漸變探針微帶線餽入天線、微帶線至矩形波導背對背轉接電路、T型與威金森型矩形波導功率分配器並且量測，量測的結果與模擬的結果有很好的一致性，驗證了這些設計的正確性。

In this thesis, a compact and broadband microstrip-fed antenna using the antisymmetric tapered probe with triangular coupling element is proposed. The design is compact since the microstrip line signal could be directly fed into the antenna through the antisymmetric tapered probe. Besides, the proposed antenna has a broadband bandwidth in which the magnitude of the reflection coefficient is smaller than –10 dB, covering from 9.24 GHz to 18.14 GHz. Furthermore, the radiation pattern is omnidirectional among this frequency range.
In order to realize a compact and broadband microstrip line to rectangular waveguide transition, the microstrip-fed antenna using the antisymmetric tapered probe is placed directly into the rectangular waveguide. The fractional bandwidth of this transition for which the return loss is larger than 15dB covers from 8 to 13 GHz, encompassing the whole X-band (8.2–12.4 GHz). The corresponding IL in this frequency range is better than 0.22 dB. As compared with the transition using the tapered CPS probe and the transition using the short-end tapered probe, the 15-dB FBW is increased and the circuit size is reduced.
In order to realize a compact and broadband rectangular waveguide power divider, three transitions using the antisymmetric tapered probe are integrated with the T-junction. The rectangular waveguide power divider using the T-junction with antisymmetric tapered probe has a broadband response that the reflection coefficient of the input port is smaller than –15 dB and the transmission coefficients of the output ports are around –3.2 dB from 8.48 GHz to 12.04 GHz.
In order to advance this power divider as a power divider/combiner, the Wilkinson power divider is used to replace the T-junction. The rectangular waveguide power divider/combiner using the Wilkinson power divider with antisymmetric tapered probe has small reflection coefficients, equal power division, and good isolation for all ports among the X-band. The reflection coefficient of the input port is smaller than –15 dB and the reflection coefficients of the output ports are smaller than –12.6 dB from 8.44 GHz to 12.6 GHz, covering the whole X-band. Besides, the transmission coefficients of the output ports are around –3.3 dB and the isolation is smaller than –17.5 dB.
In order to verify the designs and simulation results mentioned above, circuits are fabricated and measured, including a microstrip-fed antenna using the antisymmetric tapered probe, back-to-back MSL to RWG transition, T-junction and Wilkinson RWG power dividers, where the measurement results are in good agreement with the simulation results.

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