Dielectric characterization using patch antennas

In this paper, complex permittivities of lossy dielectric mixtures with a wide range of permittivity values are characterized with a patch antenna using near field techniques. Permittivity range explored is from 8 to 80. Measurements are carried out in the 1-2GHz frequency range and the magnitude and phase response from reflection measurements are acquired using a Network Analyzer. Transfer functions are generated using both magnitude and phase to estimate the real and imaginary part of the permittivity. Comparative study is done for the estimation error when only one parameter is used in the estimation as opposed to using multiple parameters in the regression. Complex permittivity measurements from Agilent probe kit 85070 are used as reference values for the empirical models.