Dominant quasi-TEM mode generator for thin oversized dielectric coated rectangular waveguide

In this paper a feed circuit is proposed for oversized dielectric-coated rectangular waveguide. Feasible simulation results show the excitation of the dominant mode with an amplitude ripple less than 3 dB in oversized waveguide. Input reflection at the design frequency is suppressed to -30 dB. The bandwidth is about 7% in terms of reflection less than -20 dB.