Coupling of Dielectric Resonators to Rectangular Waveguides

A method for calculation of the coupling of a dielectric loaded resonator to a rectangular waveguide by means of a long thin slot is presented. Experimental measurements performed on several cases are compared to the calculations. Effect of the resonator´s field variation on the coupling calculations are discussed. It is shown that the small aperture theory fails to predict the coupling coefficient variation as a function of the slot length. The actual (measured) variation is predicted properly by taking into account the field distribution in the resonator.