A Miniaturized 3–10GHz 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%.