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Improved phase-ellipse method for in-situ geophone calibration

Huaibao P. Liu·L. Peselnick
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Abstract

For amplitude and phase response calibration of moving-coil electromagnetic geophones two parameters are needed, namely, the geophone natural frequency, f 0 , and the geophone upper resonance frequency f u . The phase-ellipse method is commonly used for the in situ determination of these parameters. For a given signal-to-noise ratio, the precision of the measurement of f 0 and f u depends on the phase sensitivity, f(δφ/δf) For some commercial geophones f(δφ/δf) at f u can be an order of magnitude less than the sensitivity at f 0 . In this paper we present an improved phase-ellipse method with increased precision. Compared to measurements made with the existing phase-ellipse methods, our method shows a 6- and 3-fold improvement in the precision, respectively, on measurements of f 0 and f u on a commercial geophone.

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Huaibao P. Liu, L. Peselnick. 2006-04-27. Improved phase-ellipse method for in-situ geophone calibration. https://doi.org/10.1111/j.1365-2478.1986.tb00480.x

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