Adaptive frequency-stabilization of MEMS oscillators using mode coupling

Microelectromechanical systems (MEMS) oscillators with high frequency stability hold significant potential for a myriad of applications across diverse fields. This letter delves into an adaptive frequency stabilization system designed to significantly improve the performance of MEMS oscillators. Our approach leverages the concept of mode coupling to dynamically adjust the oscillator’s frequency based on phase control, ensuring optimal stability under varying operating conditions. The MEMS oscillator comprises a nonlinear low-frequency resonator and a linear high-frequency resonator. Through mode coupling and phase control, the nonlinear resonator is harnessed to regulate the oscillation frequency of the linear resonator. Experimental results prove that by applying the proposed approach, the frequency stability of the MEMS oscillator is enhanced by nearly 700 times for long-term stability at 1000 s. Additionally, in the scenario with varying temperature, the system also effectively improves the frequency stability by over 1000 times at 802 s.