Millimeter-wave properties of TGS ferroelectric crystal near phase transition

The temperature dependencies of both reflection and absorption coefficients measured at the two frequencies of 37.5 and 38.4 GHz has been compared to the real and imaginary parts of the microwave dielectric permittivity of TGS crystal near phase transition. It was shown that there is a good agreement between the temperature behavior of microwave dielectric permittivity and the wave characteristics measured at the same frequencies. It means that one can predict the dielectric properties of ferroelectrics measuring only wave characteristics modified by the presence of the crystal.