Acoustic sensors for remote pressure control

Abstract

Sensors based on surface acoustic wave (SAW) delay lines are considered, incorporating transmitting-receiving and reflective interdigital transducers (IDTs). The dependencies of the SAW reflection coefficient on the type and magnitude of the load have been investigated. A composite delay line is proposed, in which the phase of the reflection coefficient depends on the pressure magnitude that causes displacement of the reflective IDT relative to the transmitting-receiving one, since they are located on different substrates. Structural schemes of interrogation devices are also presented.