With the advantages of small size and low cost, MEMS gyroscopes have been used in a variety of applications such as image stabilization, gaming control, and motion tracking for mobile or wearable devices. One potential application for MEMS gyroscopes is indoor navigation. This minimizes the infrastructure requirements compared with other approaches with electromagnetic reference beacons. However, recent consumer MEMS gyroscopes are still orders away from achieving navigation grade performance.
Frequency-modulated (FM) gyroscopes achieve good scale factor stability and high dynamic range while consuming very low power. Continuous time mode-reversal modulates the signal away from low frequency drift such as resonance frequency. This report presents a MEMS-ASIC integrated FM gyroscope, which achieves a bias stability of 5.7◦/hr at an averaging time of 2048 s and scale factor stability of 27 ppm at 7680 s while consuming only 110μW for single-axis gyroscope operation. In one experiment, the scale factor drifts less than ± 150 ppm over 50 hours at room temperature. The gyroscope has low temperature dependency for both bias and scale factor without any temperature compensation. The unique low-power and high-stability features make it attractive for always-on indoor-navigation.
Also presented in the thesis are derivations of the position error as a function of gyroscope noise specifications and an investigation of the frequency mismatch of the nominally symmetric transducers used in the FM gyroscope experiments.