本論文使用偶極槽線天線以及領結型槽線天線來設計共面波導至矩形波導轉接，並且應用所設計的共面波導至矩形波導轉接，進一步形成共面波導至矩形波導功率分配器。我們所採用的矩形波導為標準的WR-90矩形波導，操作頻帶涵蓋X頻帶 (8.2-12.4 GHz)。
關於共面波導至矩形波導轉接，使用偶極槽線天線的共面波導至矩形波導轉接，其反射損耗在大於15 dB的頻寬大約為24.3 %，在這個頻寬之內，其穿透損耗都小於0.17 dB。為了加大頻寬，我們使用領結型槽線天線來實現共面波導至矩形波導轉接，這結構的反射損耗在大於15 dB的頻寬大約為27.2 %，稍微大於使用偶極槽線天線的共面波導至矩形波導轉接的頻寬，在這個頻率範圍內，其穿透損耗都小於0.17 dB。
關於共面波導至矩形波導功率分配器，使用偶極槽線天線的共面波導至矩形波導功率分配器，其反射損耗大於15 dB的頻寬大約為39.8 %，在這個頻寬之內，其穿透損耗都在3.08~3.27 dB之間，兩個輸出端的隔離度都在4.8~6.75 dB之間。使用領結型槽線天線的共面波導至矩形波導功率分配器，其反射損耗大於15 dB的頻寬涵蓋整個X-band，在X-band之內，其穿透損耗都在3.05~3.29 dB之間，兩個輸出端的隔離度都在5.48~6.87 dB之間。
為了驗證以上的結果，我們以背對背的方式，串接兩個共面波導至矩形波導轉接或者兩個共面波導至矩形波導功率分配器，電路製作好之後，我們使用Agilent E8326B PNA向量網路分析儀結合HP X11644A矩形波導校準件進行量測，量測所得的結果與模擬結果滿一致的，由此可以驗證這些設計的正確性。

This thesis proposes an idea of using a dipole slot antenna or a bow-tie slot antenna to realize coplanar waveguide (CPW) to rectangular waveguide (RWG) transitions. Furthermore, the CPW to RWG transitions are extended to the design of CPW to RWG power dividers. The RWG adopted here is the standard WR-90 rectangular waveguide where the operation band of this waveguide covers the whole X-band (8.2-12.4 GHz).
Regarding the CPW to RWG transitions, the CPW to RWG transition realized by using the dipole slot antenna has a bandwidth of 24.3 % for which the return loss (RL) is larger than 15 dB, where the corresponding insertion loss (IL) in this frequency range is smaller than 0.17 dB. On the other hand, the CPW to RWG transition realized by using the bow-tie slot antenna has bandwidth of 27.2 % for which the RL is larger than 15 dB, where the corresponding IL in this frequency range is smaller than 0.17 dB. It can be seen that the transition realized by using the bow-tie slot antenna has a broader bandwidth than that realized by using the dipole slot antenna has.
Concerning the CPW to RWG power dividers, the CPW to RWG power divider realized by using the dipole slot antenna has a bandwidth of 39.8% for which the RL is larger than 15 dB, where the corresponding IL in this frequency range varies slightly from 3.08 to 3.27 dB. Also, the isolation between the output ports in this frequency range varies from 4.8 to 6.75 dB. On the other hand, the CPW to RWG power divider realized by using the bow-tie slot antenna has a bandwidth covering the whole X-band for which RL is larger than 15 dB, where the corresponding IL in the X-band varies slightly from 3.05 to 3.29 dB. Also, the isolation between the output ports in this frequency range varies from 5.48 to 6.87 dB.
The design results of the CPW to RWG transitions or the CPW to RWG power dividers mentioned above are supported through measuring the implemented real circuits. Two CPW to RWG transitions or two CPW to RWG power dividers are connected back-to-back in order to facilitate the measurements. The fabricated circuits are measured through using the Agilent E8326B PNA after calibrating with HP X1164A RWG calibration kits. All the measurement results agree with the simulation results, which verify the correctness of our designs.

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