Quality factor and resonant frequency measurement by ARMA process identification of randomly excited MEMS/NEMS cantilever

Microcantilever based sensors are very promising devices for biochemical applications. They usually operate in two modes. In the first one a microcantilever static bending induced by the surface stress is observed, while in the second mode, resonant frequency shift caused by mass loading is measured. In the paper, the real-time noise analysis (RTNA) technique is presented. It is based on ARMA process modeling. The estimated model parameters are used for the calculation of the eigenfrequency and quality factor of a given vibration mode. The description of the entire procedure is presented as well as the results of an analysis of stochastic response of an electromagnetically excited cantilever. These results confirm validity of the proposed ARMA model and show the expected estimation errors. The proposed solution is an interesting option, especially, if the simplicity and the cost of the measurement system are important issues.