A Miniaturized 3–10 GHz Time-Domain Contact-Based Dielectric Spectroscopy System

In this paper, a miniaturized time-domain dielectric spectroscopy system in 3-10 GHz range is presented. The proposed system consists of a UWB transmitter, a sensor, and a high speed oscilloscope as a receiver. In the UWB transmitter, a wave-shaping circuit with an SRD and a short-circuited stub generates the baseband UWB signal, a mixer and an amplifier upconvert and amplify the baseband UWB signal and apply it to the sensor in 3-10 GHz range. The sensor is constructed using a periodic structure of 8 downsized cells, while the material under test (MUT) is inside a container located on top of the sensor. Using the phase differences (Δφ) of five reference MUTs, a polynomial relationship is fitted between ε
^'
and Δφ to model the system response. Employing that model, the ε
^'
of an unknown MUT is extracted from its measured Δφ with an error of 1.94%.