Application in Measuring the Microwave Complex Permittivity of Cylindrical Dielectric by Using a Terminal Loaded Coaxial Probe

A new terminal loaded probe which can measure the complex permittivity of dielectric has been proposed in this paper. We have analyzed the effect of some high order TM modes brought by the discontinuity of the dielectrics on the interface in the coaxial cable to the reflectance. According to the mode-matching method, the analysis of the electromagnetic in the coaxial and the dielectric loaded on the terminal of the probe is performed. With the result, we have measured some dielectrics (silicon and Teflon) at and under C band and have compared the metrical value with the computational value and they were nearly the same, and it can advance the precision. This method can be used in measuring the solid material and the liquid as well.