A Wideband Sensor for Complex Permittivity of Carasau Bread Dough Based on a Double Ridge Waveguide

This work aims at the preliminary design of a microwave devices to perform indirect measurements of the complex permittivity of the Carasau bread, a traditional food product from Sardinia (Italy). To this purpose, the complex dielectric permittivity of doughs is measured with open-ended coaxial probe in the range 0.5-8.5 GHz and the spectra fitted to a third-order Cole-Cole model. The acquired data are then used to numerically study the microwave signal propagation in the designed a double ridge waveguide and investigate different sample configuration in order to obtain a wideband transmission performance.