Analysis of a passive radio frequency excited acoustic transducer

In this paper, the physical processes that govern the operation of a passive acoustic transducer are analyzed and modelled. The wireless battery-free transducer derives its power from an externally applied electromagnetic field generated by a radio transmitter. The audio signal is encoded in the backscattered electromagnetic field. Electro-Mechano-Acoustical analogies are developed and presented. Power generation, sound transduction and radio frequency backscatter transmission of the audio signal are examined. The resonant frequency of the passive acoustic transducer derived from this analysis is similar to other resonant frequencies reported in the literature.