Calibration for CHAMP Accelerometer Data Based on Crossover Points of the Satellite

The German Challeging Minisatellite Payload(CHAMP) was launched in July 2000. It is the first satellite that provides us with position and accelerometer measurements, with which the gravity field model can be determinated. One of the most popular method for geopotential recovery using the position and accelerometer measurements is the energy conservation method. The main aim of this paper is to determinate the scale and bias parameters of CHAMP accelerometer data using the energy conservation method. The basic principle and mathematical model using the crossover points of CHAMP orbit to calibrate the accelerometry data are given based on the energy balance method. The rigorous integral formula as well as its discrete form of the observational equation is presented. This method can be used to estimate only one of the scale and bias parameters or both of them. In order to control the influence of outliers, the robust estimator for the calibration parameters is given.