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IEEE Transactions on Microwave Theory and Techniques
Volume 48 Number 12, December 2000

Table of Contents for this issue

Complete paper in PDF format

A Wireless Pressure-Measurement System Using a SAW Hybrid Sensor

Gernot Schimetta, Member, IEEE Franz Dollinger and Robert Weigel Senior Member, IEEE

Page 2730.

Abstract:

A pressure-measurement system based on surface-acoustic-wave (SAW) sensors is presented in this paper. Since SAW sensors are powered by the energy of the RF field, no battery is required, which is a major drawback of conventional microcontroller-based telemetry systems. A successful combination of a SAW reflective delay line with a high-Q capacitive pressure sensor is shown. With a new way of matching the sensor impedance to the SAW reflector impedance, both a high signal-to-noise ratio and a high signal dynamic are achieved, which supports accurate signal evaluation. As an example of realization, the prototype of a tire pressure sensor unit is presented.

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