Guided modes in shielded slot transmission line

Guided modes in a shielded slot transmission line were analyzed. This transmission line consists of slotted metal strips inserted in a below cutoff parallel metal plate waveguide. The TEM mode can propagate in the slot area as the lowest dominant mode, while the higher modes may propagate in the metal strip regions from the calculated results based on the transverse resonant method. A design diagram of the shielded slot transmission line was provided by the numerical results of the cutoff wavelength of the higher modes.