Amplitude-modulated resonant accelerometer employing parametric pump
Hemin Zhang, Dongyang Chen, Milind Pandit, Jiangkun Sun, Chun Zhao, Ashwin A. Seshia
Abstract
This paper demonstrates a resonant accelerometer employing weakly coupled resonators for inertial force transduction. An ultra-low virtual mode coupling is established by employing the parametric pump in the coupled resonators to enhance the parametric sensitivity. This paper proposes that the amplitude of the driven resonator can be used for monitoring the input acceleration in a limited linear range around the veering point. In addition to the high-sensitivity improvement, the measurement complexity is also considerably reduced compared to the previous amplitude ratio readout sensors. The sensitivity is adjustable by changing the parametric pumping amplitude. The experimental results show that the noise power spectral density is ∼230 ng/√Hz, which is the best reported noise floor for resonant accelerometers based on weakly coupled resonators.