Permittivity measurements and associated uncertainties up to 110 GHz in circular-disk resonator method

We have measured the complex permittivity of plate samples and evaluated those uncertainties up to 110 GHz by using a balanced-type circular-disk resonator. By an electromagnetic excitation in the center from coaxial lines, only the TM
_0m0
modes are selectively excited, so broadband measurements from 5 to 110 GHz can be performed by a single resonator by utilizing higher order modes. We have evaluated measurement uncertainties by rigorously considering the uncertainty propagations of measured S-parameters and dimensions. The obtained results are compared with those obtained by the split-cylinder resonator method, and they agree rather well with each other within the ranges of uncertainties.