Accuracy Evaluation Method of GOCE SGG Data Based on Satellite Crossovers

method of accuracy evaluation using crossover differences is studied.A revised formula for accuracy evaluation is proposed to overcome the shortcomings of the classic formula.The influence of the systematic errors on the accuracy evaluation is analyzed.The calibration of scale factor by using the existing gravity field model is proposed.A numerical example from the simulated Tzz of GOCE satellite is performed.The results show that the new method can reasonably evaluate the accuracy of data with the relative error of 5%,which is far better than the classic method with the relative error of 13%.The scale factor can efficiently calibrated using the existing gravity field model with no more than 2% of relative error,and the average of relative errors is about 0.9%.The result of accuracy evaluation is almost the same between the cases with and without systematic errors.