Miniature Short-Term Navigation Grade Quartz MEMS Accelerometer

Abstract

EMCORE Corporation has demonstrated a new quartz micromachined accelerometer based on differential frequency modulation (FM) principle of operation. This development is based on the conventional EMCORE/Systron Donner quartz accelerometer, which used in SDI500 tactical grade IMU. Several design solutions have extended the performance of the device to achieve high-end tactical grade and in-run navigation grade. Experimental characterization of the accelerometer revealed velocity random walk of 500 nG/rt-hz (which is > 100 times better than EMCORE's current accelerometer), bias instability of 300 nG at stable ambient temperature. In parallel with lowering accelerometer’s noise characteristics, a new bias calibration method across dynamic temperature environments has been implemented. This approach enabled us to improve bias stability over dynamic temperature (-55 °C to +85 °C) to better than 100 uG (+\sigma), calibrated SF better than 20 ppm, and BW ~ 150 or 300 Hz.