GOCE Precise Orbit Determination Using Pure Dynamic Method and Reduced Dynamic Method

Abstract

The basic principles and mathematical models for pure dynamic orbit determination and reduced dynamic orbit determination are reviewed briefly. The GOCE orbit determination accuracies of pure dynamic method (PDM) and reduced dynamic method (RDM) are compared using different gravity field model with different degree and order (d/o). The computational results show that the orbit accuracies of the two methods using GOCO02S is obviously higher than those of EIGEN-5C and a little superior to those of ITG-GRACE2010S with the same d/o. The orbit determination accuracies of PDM and RDM using gravity field model with 150 and 180 d/o are greatly higher than those with 120 d/o. The SST observation, common-mode acceleration and attitude quaternion from 16/11/2009 to 18/11/2009 are used for GOCE orbit determination. The results show that the orbit accuracy of using PDM is about 11 cm, which can meet the accuracy requirement of GOCE rapid science orbit (RSO). The orbit accuracy of using RDM is about 2.2 cm, which is very close to the accuracy requirement of GOCE precise science orbit (PSO). There is still space of accuracy improvement since the GOCE satellite antenna phase center variation (PCV) is not estimated and considered in PDM and RDM.KeywordsGOCEPrecise orbit determinationPure dynamic methodReduced dynamic method