Through-Wall Acoustically Linked Temperature Sensor

In this paper we demonstrate the possibility of “through-wall” temperature measurement via the acoustically coupled PZT transducers operated at the frequency of 12 MHz. Temperature measurement was done by thermistor attached to hotplate and electrically connected via the matching network to the PZT transducer. Temperature dependent electrical impedance variation of PZT on the one side of the wall leads to changing of the reflection coefficient S 11 on the PZT transduce from other side of the metal wall and can be easily detected by the network analyzer.