Dielectric-property determination from measurement of magnitude of reflection and coupling coefficients of coupled antennas

This paper presents a dielectric-property determination technique that measures the magnitudes of the reflection and coupling coefficients of coupled antennas. They are plotted on the epsiv_r ^psila epsiv_r ^rdquo plane, and the intersection of these two quantities provides the values of epsiv_r ^psila and epsiv_r ^rdquo where epsiv_r ^psila is the real part and epsiv_r ^rdquo is the imaginary part of the relative complex permittivity. Measurement results of water validate the effectiveness of the proposed technique. This technique provides a compact measurement system and is suitable for localized dielectric determination.