Nonlinear system identification of a MEMS dual-backplate capacitive microphone by harmonic balance method

Journal Article

This paper presents the nonlinear identification of system parameters for a capacitive dual-backplate MEMS microphone. First, the microphone is modeled by a single-degree-of-freedom (SDOF) second order differential equation with electrostatic and cubic mechanical nonlinearities. A harmonic balance nonlinear identification approach is then applied to the governing equation to obtain a set of algebraic equations that relate the unknown system parameters to the steady-state response of the microphone under the harmonic excitation. The microphone is experimentally characterized and a nonlinear least-squares technique is implemented to identify the system parameters from experimental data. The experimentally extracted bandwidth of the microphone is over 218 kHz. Finally, numerical simulations of the governing equation are performed, using the identified system parameters, to validate the accuracy of the approximate solution. The differences between the properties of the integrated measured center velocity and simulated center displacement responses in the steady state are less than 1%. Copyright © 2005 by ASME.

Full Text

Duke Authors

Cited Authors

  • Liu, J; Martin, DT; Kadirvel, K; Nishida, T; Cattafesta, LN; Sheplak, M; Mann, BP

Published Date

  • 2005

Published In

Volume / Issue

  • 256 /

Start / End Page

  • 269 - 276

International Standard Serial Number (ISSN)

  • 0160-8835

Digital Object Identifier (DOI)

  • 10.1115/IMECE2005-82880