Acoustically Coupled Passive Wireless Sensor System With Mechanical Resonant Sensor

Abstract

Aviation and aerospace are challenging applications for instrumentation technologies. Under these harsh environmental conditions, passive wireless sensor technology has proven itself to be functional. However, if an electrically conductive media is present between the read-out unit and the wireless sensor, electromagnetic waves will be strongly attenuated. In contrast, acoustic waves have good transmission properties through fluid or solid media and are, therefore, suitable under such conditions. In this contribution, we propose a novel concept of an acoustically coupled passive wireless sensor system with a robust, purely mechanical resonator as sensing element. The novel concept combines the passive sensor technology with an acoustic communication channel and a robust mechanical resonator serves as sensing element, which can be directly excited with an acoustic wave. The concept is implemented with an electromechanical transducer and a mechanical resonator at an operation frequency of 33kHz.