Portable SAW Impedance Sensor Using a 1-Port Resonator Approach†
AbstractAll actually used SAW sensors have in common that they analyze the transmission characteristics of propagating SAWs. Here, a portable device using the SAW-based impedance sensor type based on one interdigital transducer (IDT) simultaneously as SAW generator and sensor element (1-port approach) is presented. The input port reflection coefficient S11 is measured at the IDT instead of the commonly used S21 transmission forward gain parameter. As a novelty, the so far required expensive vector network analyzer (VNA) is replaced by a hand-held device to measure the impedance spectrum of the SAW sensor by RF-gain-phase meters. The pivotal aspect of the portable system is the transfer of the sophisticated high frequency approach into a quasi-static one. This enables the use of simple lumped electronics without the need of impedance matching circuits. Proof-of-concept was carried out by measuring conductivities of phosphate-buffered solutions (PBS) and viscosities of glycerin. Sensitivities for conductivity of 64 Hz/S cm−1 and for viscosity of 122 mΩ/mPas were obtained, respectively.
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Nguyen, V.H.; Peters, O.; Serve, S.; Schnakenberg, U. Portable SAW Impedance Sensor Using a 1-Port Resonator Approach. Proceedings 2017, 1, 361.
Nguyen VH, Peters O, Serve S, Schnakenberg U. Portable SAW Impedance Sensor Using a 1-Port Resonator Approach. Proceedings. 2017; 1(4):361.Chicago/Turabian Style
Nguyen, Vu Hoa; Peters, Oliver; Serve, Sam; Schnakenberg, Uwe. 2017. "Portable SAW Impedance Sensor Using a 1-Port Resonator Approach." Proceedings 1, no. 4: 361.
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