本論文主要係使用共平面波導研製多型微波及毫米波多導線交趾式耦合器。微波頻段之多導線交趾式耦合器實現於印刷電路基板，並將所研製之耦合器應用於設計寬頻平衡式放大器，由於本論文所研製之多導線耦合器係由非對稱雙線耦合線演化而來，為了準確地萃取出非對稱耦合線之c與π模態阻抗，本論文提出一電腦模擬輔助設計方法，以克服目前商用電磁全波模擬軟體之模擬限制。由實驗結果可驗證本論文提出之設計步驟不僅有利於多導線交趾式耦合器之設計，且可同時於兩輸出埠上獲得一寬頻且平坦的相位差特性。此外，90相位頻寬特性優異之耦合器進一步應用於實現平衡式放大器，使其具有109 %輸入及輸出端反射損失頻寬。毫米波頻段之多導線交趾式耦合器則使用整合被動元件(IPD)製程製作，因兩正交模態在IPD不均勻介質中傳播將導致不同之相位速度，本論文提出三型具相速度補償之電路結構。由模擬與量測結果驗證得知，所提出之電路結構可有效改善c與π模態相位常數差異。

This thesis develops a variety of the microwave and millimeter-wave multi-conductor interdigitated couplers using the coplanar waveguides (CPWs). For microwave range, the CPW multi-conductor interdigitated couplers are realized on the printed circuit board (PCB) substrate, and then applied to implement a balanced amplifier with a broadband return loss bandwidth. Since the multi-conductor couplers are evolved from asymmetrical two-conductor coupled-line, to accurately extract the c- and π-mode impedances of the multi-conductor asymmetrical coupled lines, a simulator-aided design method is proposed in this thesis to overcome the limitation of the commercial electromagnetic simulator. The experimental results demonstrate that the proposed design procedures not only reduce the design complexity and increase the design flexibility, but also develop couplers with wideband and flat quadrature phase responses between output ports. Moreover, as the developed interdigitated couplers are applied to implement a balanced amplifier, one can achieve a 109 % 10-dB return loss bandwidth. For millimeter-wave range, the CPW multi-conductor interdigitated couplers are implemented using the integrated passive device (IPD) technology. Since the IPD nonhomogenous medium will lead to different c- and π-mode phase velocities, this thesis proposes three circuit structures to compensate the difference of c- and π-mode phase constants. The effectiveness of newly proposed structures has been experimentally demonstrated.

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