Prediction and removal of rotation noise in airborne EM systems
Terence Kratzer 1 2 James Macnae 1
+ Author Affiliations
- Author Affiliations
1 RMIT University, GPO Box 2476, Melbourne, Vic. 3001, Australia.
2 Corresponding author. Email: terence.kratzer@rmit.edu.au
Exploration Geophysics 45(3) 147-153 https://doi.org/10.1071/EG13064
Submitted: 23 July 2013 Accepted: 28 January 2014 Published: 12 March 2014
Abstract
We aim to eliminate or reduce significant impediments to conductive target detection and conductive cover penetration in airborne electromagnetic (AEM) systems. Existing limitations come from the very high noise encountered at low base frequencies, caused by rotations of vector magnetic field sensors in the Earth’s magnetic field. We use the output of tri-axial rotation-rate sensors to predict and subtract the rotation noise from rigidly coupled ARMIT magnetic field sensors. The approach is successful in reducing rotation noise by one to two orders of magnitude at low frequencies.
Key words: airborne EM, low-frequency, motion noise, rotation noise.
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