An electromagnetic wave mode transducer for TE20 mode in substrate integrated waveguide

A novel electromagnetic wave mode transducer for TE20 mode in a substrate integrated waveguide is proposed. The transducer contains two basic parts: the over-moded waveguide cavity section and the fundamental mode rejection section. To obtain a wideband mode transducer, an over-moded waveguide cavity is designed with multiple frequencies resonance. In the rejection section, an array of cylindrical metallic posts is installed along / next to the midline in the longitudinal direction of the waveguide to suppress the transmission of the fundamental mode. The transducer has the merits of low loss, wideband, and good mode purity. Moreover, the transducer can be easily fabricated and integrated with other planar circuits.