Immunity to Temperature Fluctuations in Weakly Coupled MEMS Resonators

Eigenstate variations in weakly coupled MEMS resonators have been shown to exhibit common mode rejection capabilities that make them immune to environmental fluctuations to first order. In contrast to previous work on this topic, this paper shows in-depth experimental characterization of the resonator system at a range of temperatures between 35°C and 60°C using amplitude ratio as the readout metric. An analysis is conducted on the impact of the cross-sensitivity to temperature variations on the input-referred stiffness perturbation for the resonator system and this is compared to the variations in the frequency shift output metric within the same device. These results show 2 orders of magnitude improvement in temperature immunity for the amplitude ratio readout metric as compared to the conventional frequency shift method.