Effects on the Performance of Parametric Loudspeaker Caused by Nonideal Ultrasound Transducer

摘要

In this paper, we report the effects on the performance of a parametric loudspeaker caused by a nonideal ultrasound transducer. The frequency contents of self-demodulated secondary wave pressure for the nonideal ultrasound transducer are first derived on the basis of Berktay's solution. Then, according to the relationship between the input signal and the envelope of primary wave pressure, the harmonic distortion and intermodulation distortion are obtained for different modulation techniques. Simulation experiments show that in the case of using the double-sideband amplitude modulation (DSB-AM) technique, the amplitudes of the fundamental frequency and intermodulation distortion components are affected by both the phase and magnitude response of the ultrasound transducer, whereas the harmonic distortion component is only affected by the phase response. In the case of using the single-sideband amplitude modulation (SSB-AM) technique, the amplitudes of the fundamental frequency component and intermodulation distortion components are only affected by the magnitude response of the transducer.