Gravity Gradiometer Output Noise Suppression Based on Minimum Mean Square Error Estimation

Rotating accelerometer gravity gradiometer (RAGG) has significant applications in resource exploration and auxiliary navigation. However, the RAGG output noise significantly reduces the measurement accuracy and reliability of the instrument. This paper addresses the suppression of RAGG output noise by installing two RAGG units to perform simultaneous measurements and using the minimum mean square error (MMSE) method. The output noise of the RAGG is 40 E/√Hz when measured individually, nevertheless it can be reduced to 30 E/√Hz using the MMSE estimation, achieving a 21% noise reduction. Furthermore, this method shows an 8% improvement compared to the direct averaging of two RAGG units, which yields 33 E/√Hz. Additionally, we validated the effectiveness of this method through calibration experiments. The calibration experiment's RMSE was reduced from 12 E to 9 E, consistent with the noise suppression effect, thereby enhancing the accuracy of gravity gradient measurements.