SAW-based radio sensor systems for short-range applications

Wireless autonomous surface acoustic wave (SAW) sensors offer high flexibility for modern sensor systems. Because no battery or wiring is required for power-supply and communication tasks, they can be advantageously employed for nearly all kinds of short-range identification and measurement applications, where the use of conventional sensors, e.g., on moving or rotating parts or in industrial process chambers. Here, the basics of SAW-based radio sensor systems are reviewed and different examples out of a manifold of possible applications are given. Wireless SAW identification and sensor systems operate stable and maintenance free over many years even in harsh industrial environments. With a fast readout of only a few microseconds, a readout-distance of up to several meters, and a high sensor stability, even at temperatures above 200 °C, these highly flexible SAW-based radio systems are ideally suited for a multitude of measurement tasks in industrial, automotive, transportation, and domestic applications.