Filtering method of airborne gravity gradiometer signal based on EMD

Abstract

Gravity gradiometer sensor performance, platform instability and electronic circuit noise can cause serious influence on the weak gravity gradiometry signal, and the noise level is usually one or several times of gravity gradient signal. This paper put forward a method to resolve this problem according to the characteristics of the signal. First of all, filtrate the gravity gradient signal with a band-passing filter. Then, demodulate the output signal of the band-passing filter, at last, remove the gravity gradiometry noise with the empirical mode decomposition (EMD) method. Then the gravity gradiometer signal was tested on the hardware-in-the-loop simulation platform. The experiment results verify that the various harmonic noise can be removed with the method proposed above, and the gravity gradient signal accuracy and gravity gradient space resolution is further improved, the good properties of the method is of high practice and maneuverability.