Wireless measurement of temperature using surface acoustic waves sensors.

Surface acoustic wave (SAW) devices can be used as wireless sensor elements, called SAW transponders, for measuring physical quantities such as temperature that do not need any power supply and may be accessed wirelessly. A complete wireless sensor system consists of one or more such SAW transponders and a local radar transceiver. The SAW transponder receives an RF burst in the VHF/UHF band transmitted by the radar transceiver.