寬頻 3 dB 舷側式方向耦合器設計

Abstract

本論文將介紹兩個寬頻 3 dB 舷側式 (broadside-coupled) 方向偶合器 (directional coupler) 之設計，並製作與量測。兩個偶合器分別工作於 1~9 GHz 與 2~18 GHz 頻段。前者採用多段式 (multi-section) 結構，而後者乃採用非均勻式 (non-uniform) 結構。為了獲得 90 度相位差的特性，兩者皆為對稱性結構。另外為了獲得較佳的性能並實際製作，電路中同時也採用了所謂的縱排式 (tandem) 結構。經過一番製作與量測，得到了滿意的量測結果。與理論之預測值之間也有相當的一致性。

Tow broadband 3 dB directional couplers using broadside-coupled striplines are presented in this thesis. They were designed to work at frequency bands of 1~9 GHz and 2~18 GHz respectively. The one which works at the frequency band of 1~9 GHz is with multi-section configuration and the other one working at higher frequency band, 2~18 GHz, is with non-uniform configuration. In order to obtain quadrature characteristics, both couplers are symmetric. Besides, for better performance and practical realization, tandem configuration has been adopted. The designed circuits were fabricated and measured. There is a very well agreement between the measured results and the theoretical predictions.