Research on Kalman filter method for weak signal extraction of airborne gravity
WANG Guan-Xin1,2(), LUO Feng1,2, ZHOU Xi-Hua1,2, YAN Fang3
1. Key Laboratory of Airborne Geophysics and Remote Sensing Geology, Ministry of Natural Resources, Beijing 100083, China 2. China Aero Geophysical Survey and Remote Sensing Center for Natural Resources, Beijing 100083, China 3. Beijing Institute of Automatic Control Equipment,Beijing 100074,China
Airborne gravimetry uses aircraft as a carrier to collect data of gravity field. Due to the influence of air flow, flight state and body vibration, the original data of airborne gravity measurement contain a large amount of noise, and the SNR is as high as the grade of several thousand to ten thousand. This becomes a technical problem for the development of airborne gravity measurement system to obtain the weak gravity signal from the original measurement data. In this paper, the general Kalman filter formula with certain control was adjusted for adaptability based on airborne gravity measurement system, the mathematical model of the airborne gravity anomaly was established, and the Kalman filter state equation was proposed for measuring principle of the system. Finally, the authors solved the problem of gravity signal and differential GNSS signals matching and airborne gravity of weak signal extraction. After the test of airborne gravity measurement data, the proposed airborne gravity data solution method can be used to solve airborne gravity anomalies with high accuracy, and the result is better than the FIR low-pass filter (currently used in engineering) solution results, which promotes the development of airborne gravity weak signal extraction technology.
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WANG Guan-Xin, LUO Feng, ZHOU Xi-Hua, YAN Fang. Research on Kalman filter method for weak signal extraction of airborne gravity. Geophysical and Geochemical Exploration, 2021, 45(1): 76-83.
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