Acoustic sensor for remote measuring of pressure

Abstract

The paper deals with sensors based on delay lines on surface acoustic waves (SAW), having a receiving-emitting and a reflective interdigital transducers (IDT). The dependence of the reflection coefficient of SAW on type and intensity of the load was studied. The authors propose a composite delay line in which the phase of the reflection coefficient depends on the pressure. Pressure leads to a shift of the reflective IDT relative to the transceiver, because they are located on different substrates. The paper also presents functional diagrams of the interrogator.

Keywords

• surface acoustic waves
• interdigital transducer
• delay line
• pressure sensors