DIPLEXER SYNTHESIS USING COMPOSITE RIGHT/LEFT-HANDED PHASE-ADVANCE/DELAY LINES

摘要

A diplexing apparatus and method which utilizes composite right/left-handed (CRLH) phase-advance/delay lines combined with a coupler. By engineering CRLH- based transmission lines with desired phase responses at two arbitrary frequencies of interest, the connected CRLH delay line and/or CRLH coupler are excited in a manner such that signals at designated frequencies are separated to the corresponding output ports of the hybrid coupler. Benefits of the apparatus include elimination of design complexities such as optimization of the interconnection junctions and the harmonic spurious suppression involved in conventional filter-based diplexers. In addition, channel isolation is beneficially achieved from the isolation property of directional couplers. Measured insertion loss on the implementations was found to be less than 1 dB, with isolation greater than 20 dB in the dual bands. A high level of agreement was observed between simulated and measured results.