以集總與分散式元件設計任意功率分配之旁枝耦合器

Abstract

本論文提出分析與設計方式，以集總元件實現具有寬頻、任意功率分配之三級旁枝耦合器。藉由奇偶模分析，可知調整旁枝的傳輸線阻抗控制旁枝耦合器的功率分配。同時，在一定的功率分配下，頻寬的大小可以理論預測。本論文進一步利用集總與分散式元件，以縮小三級旁枝耦合器的面積，並比較純以集總元件實現之電路和集總與分散式元件實現之電路之間的差異。本論文實作兩電路，以驗證本文之設計，量測數據與模擬結果相當一致。

This thesis designs a 3-section wideband branch-line coupler with an arbitrary power division. Through the even/odd mode analysis, the arbitrary power division can be achieved by controlling the characteristic impedances of the branch lines. Meanwhile, for a specified power division, the fractional bandwidth can be predicted theoretically. The 3-section branch-line couplers are implemented by lumped elements and lumped distributed elements to reduce the circuit size. Theoretical analysis is validated by measurement results of experimental circuits.