Measurement of dielectric properties of medium loss samples at X-band frequencies

This work describes and evaluates a technique for determining dielectric
properties, and presents results of dielectric measurement of some substances. Dielectric
properties of some known dielectric materials are first measured and verified with our
technique and then applied to conducting polymer materials. A non-destructive method
based on the shift in resonance frequency and quality factor measurement of a resonant
cavity placing a small-sized sample is used. Dielectric constant and loss factor
measurement is performed with the aid of Spectrum Analyzer in the frequency range
from 8GHZ to 12GHz. 3-D EM simulation studies using HFSS 11 software of the cavity
with loading is compared with the measurement. The results indicated that using the
resonant cavity with the technique is suitable for dielectric parameter measurement for
small shaped medium loss samples having thickness in the range 4-6mm at X-Band
frequencies.