UNIQUE PERMITTIVITY DETERMINATION OF LOW LOSS DIELECTRIC MATERIALS FROM TRANSMISSION MEASUREMENTS AT MICROWAVE FREQUENCIES

OpenAlex İngilizce

A non-resonant microwave method has been proposed for accurate complex permittivity determination of low-loss materials. The method uses two measurement data of the magnitude of transmission properties of the sample. While the flrst datum must correspond to a frequency point resulting in a maximum magnitude of transmission properties, the other can be any datum at a frequency difierent than the flrst datum and not far distant from the flrst datum. Two closed-from expressions are derived for a good initial guess using the above data. The limitations of each expression are discussed. The method has been validated by transmission measurements at X-band (8.2{12.4GHz) of a low-loss sample located into a waveguide sample holder.