本論文中利用散佈式耦合的饋入技術與步階式阻抗共振器(stepped-impedance resonator, SIR)實現了多頻雙工器的設計，由於散佈式耦合的饋入技術的低負載效應，因此不需要複雜的匹配網路來設計多頻帶的電路。 本論文前三個電路分別為雙頻雙工器、三頻雙工器和四頻雙工器，電路架構包含了二分之一波長步階式阻抗共振器、共用的輸入饋入線和輸出饋入線。每個通帶皆由一對共振器控制可增加設計自由度，由於散佈式耦合饋入技術的低負載效應，使得每個通帶可以分別設計再將其整合在一起。此三個電路皆具有高隔離度及寬止帶的特性，在隔離度的部分可以達到29 dB以上，20-dB止帶可達到7.6倍的最低操作中心頻率。 在最後一個電路中，利用散佈式耦合饋入架構與兩對步階式阻抗共振器設計雙頻雙頻器，其中每一對共振器分別設計兩個通帶，進而達到面積縮小的效果，且通道間的隔離度仍保持在29 dB以上。 Distributed coupling technique and stepped-impedance resonators is employed to realize multi-band diplexer. Due to the low loading effect from distributed coupling technique, the proposed circuits can design many channels without the use of complicated matching network. The first three circuits include a dual-band diplexer, tri-band diplexer and quad-band diplexer. The circuits consist of half-wavelength stepped-impedance resonators, a common feeding line and output feeding lines. Each passband is controlled by respective pair of resonators to increase design freedom. Due to the low loaded effect, each passband can be design respectively, and finally combine bandpass filters into multi-band diplexers. The circuits have high isolation and wide stopband performance. The isolation is more than 29 dB and the 20-dB stopband up to 7.6 × the lowest operation center frequency. In last circuit, distributed coupling technique and two pairs of stepped-impedance resonators is employed to realize dual-band diplexer. Each pairs of resonator is designed to a dual-band performance, so the circuit size can be smaller than before. The channel isolation is more than 29 dB.
