A Novel Channel Synthesis Method for Synthesizing Tunable Diplexers with Frequency Reconfigurable Filters

With the gradual development of reconfigurable filters in high-frequency bands, the demand for duplexers and multiplexers designed for these reconfigurable filters is also increasing. Currently, the structures used to construct the connection parts of duplexers commonly include microstrip lines, waveguide T-junctions, coaxial connectors, etc. To meet the high reliability and high selectivity requirements of front-end duplexers, this paper proposes a new synthesis scheme for reconfigurable duplexers based on the principles of duplexer composition. This adjustable duplexer is composed of several directional couplers and filters, achieving seamless full-band coverage. It features high reliability and excellent channel isolation, performing well across a wide tuning range. Moreover, this synthesis method significantly facilitates the subsequent stacking and cascading of multiplexers.