Development of Diplexers Based on Dual-Mode Substrate Integrated Waveguide Cavities

摘要

Diplexers based on dual-mode Substrate Integrated Waveguide (SIAM) cavities are proposed and implemented. The dual-mode cavities not only act as a resonator for both Rx and Tx channels, but also as the interconnect between these two channels which help to realize the isolation. The dual-mode cavities resonating at TE201 and TEmmodes in our design show several advantages than those dual-mode cavities operating at TE201 and TE301 modes. Single-mode cavities are cascaded with the dual-mode cavity to realize the two-order filters for Rx and Tx channels. Two design examples are presented with a normal printed circuit board process and verified by experiments.