an inhomogeneously-loaded diaphragm in a microwave rectangular waveguide

ABSTRACTThis paper demonstrates a method to control the resonant transmission due to Fabry–Perot and Fano resonances through a dielectric‐loaded slot in a thick conducting diaphragm embedded in a rectangular waveguide. It is shown that the location of these resonances can be controlled by introducing a gap of a different dielectric constant in the middle of the slot. The two kinds of resonances are adjusted to overlap, forming a complex behaviour with potential applications as a bandpass filter with a relatively narrow notch in the passband response. The theoretical projections are confirmed through both full‐wave numerical simulations and experimental measurements. A new fabrication approach was used to overcome the shortcomings in construction that caused some discrepancies with the theory in a previous study.