Air-Coupled Ultrasonic Ferroelectret Receiver with Additional DC Voltage†
AbstractHighly sensitive air-coupled ultrasonic sensors are essential for various applications such as testing of composite materials. One of the major challenges for the development of air-coupled ultrasonic sensors is the impedance matching to air. With a lower acoustic impedance than the usual piezoelectric materials, charged cellular polypropylene film (cPP) offers better matching to air with a similar piezoelectric coefficient. The piezoelectric behaviour demonstrated by cPP comes from polarized air cells that create a permanent internal voltage. The sensitivity of the sensor varies with the application of an additional DC bias voltage. Thus, this work presents a cPP ultrasonic sensor with an improvement of up to 15 ± 1 dB on the signal-to-noise ratio.
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Gaal, M.; Caldeira, R.; Bartusch, J.; Kupnik, M. Air-Coupled Ultrasonic Ferroelectret Receiver with Additional DC Voltage. Proceedings 2017, 1, 362.
Gaal M, Caldeira R, Bartusch J, Kupnik M. Air-Coupled Ultrasonic Ferroelectret Receiver with Additional DC Voltage. Proceedings. 2017; 1(4):362.Chicago/Turabian Style
Gaal, Mate; Caldeira, Rui; Bartusch, Jürgen; Kupnik, Mario. 2017. "Air-Coupled Ultrasonic Ferroelectret Receiver with Additional DC Voltage." Proceedings 1, no. 4: 362.
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