MEMS Gyro Array Employing Array Signal Processing for Interference and Outlier Suppression
Hiroyuki Kamata, Masato Kimishima, Tsutomu Sawada, Yoshitaka Suga, Haruto Takeda, Kosei Yamashita, Shinji Mitani
Abstract
In this paper, two practical problems that cannot be ignored when forming compactly integrated MEMS IMU array at low cost using Coriolis vibration type MEMS with low power consumption - mutual vibration interference noise caused by MEMS proximity arrangement, and outlier noise caused by random telegraph signal noise - are firstly discussed. Then, we propose an easily implementable array signal processing filtering on a small FPGA that recovers gyroscope performance (angle random walk and bias instability) by suppressing the interference noise and removing the outlier noise dynamically. We fabricated 32 consumer MEMS IMU array board without IMU screening process, implemented the proposed filter, and evaluated its performance. As a result, although there are mutual interferences and a MEMS gyro sensor with poor performance, gyroscope performance (0.7mdeg/s/√Hz as angle random walk and 0.5deg/h as bias instability) which are close to the ideal array gain of 1/√32 were successfully achieved.