The printed piezoelectric loudspeaker model: A modal perspective from system identification

• Published in: Applied acoustics Vol. 174; p. 107722
• Main Authors: Quintana, Ricardo, Qiu, Xunlin, Benjamin, Aravindan, Panicker, Pramul, Schmidt, Georg, Hübler, Arved C.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-03-2021
• Subjects: Modal decomposition; Piezoelectric loudspeakers; Printed loudspeakers; System identification; Water bed effect; Water bed effect; Modal decomposition; System identification; Piezoelectric loudspeakers; Printed loudspeakers
• ISSN: 0003-682X
• DOI: 10.1016/j.apacoust.2020.107722

Mathematical models for loudspeakers are useful, especially for understanding their performance in frequency and time domain. However, each model has limitations to get accurate results. For fully printed piezoelectric polymer loudspeakers, these limitations are information shortage about materials and device performances to be modeled. This article proposes a new parameter that quantifies the frequency and decay of the energy related to the waterbed effect of each resonant frequency. It is obtained by identifying the system, then transforming it into state space model and decomposing it through Jordan canonical form. Thus, the analysis can be carried out for each mode in frequency and time space, avoiding the necessity of materials and coupling parameters, which is implicit in the measurements. The magnitude of this parameter also represents the decay of the energy of the impulse response of each mode. This is plotted to visualize the frequencies that produce the waterbed effect.