Mode Composite Folded Substrate Integrated Waveguide

This letter presents a planar mode composite folded substrate integrated waveguide (MCFSIW) that enables simultaneous propagation of the TE10 and folded TE10 (FTE10) modes. By adjusting the gap width of the MCFSIW, the cutoff frequency of the FTE10 mode can be tuned to be the same as that of the TE10 mode. The operation principle and propagation properties of the MCFSIW are analyzed. To excite the two modes independently, a simple joint feeding network (JFN) with a wide bandwidth and a high isolation is designed. A prototype of the MCFSIW with JFNs is fabricated and measured, and the measured results agree well with the simulations. The proposed MCFSIW is attractive in the development of multifunction and parallel data transmission systems.

Automated summary

This letter introduces a planar mode composite folded substrate integrated waveguide (MCFSIW) that enables the simultaneous propagation of the TE10 and folded TE10 (FTE10) modes. By adjusting the gap width of the MCFSIW, the cutoff frequency of the FTE10 mode can be tuned to match that of the TE10 mode. A simple joint feeding network (JFN) is designed to independently excite the two modes, with wide bandwidth and high isolation. The prototype of the MCFSIW with JFNs is fabricated and measured, showing good agreement with simulations.