A well-designed sensor based on split-ring resonators at microwave frequencies

In this paper, we introduce a new two-sided resonator based on the split-ring resonators to the permittivity measurement at microwave frequencies. The samples with specified thickness are placed on a well designed sensor, so that relatively large frequency offsets due to the samples can be detected to retrieve the permittivity. Analysis and simulations validate that by applying this method, permittivity can be linearly retrieved from the measured frequency offsets. The measurement setup can be conveniently calibrated with a given sample with known permittivity.