Analysis on the Accuracy of the SGP4/SDP4 Model

Based on SGP4/SDP4 model,a computer program to do the orbit determination is developed.1120 space objects with different types and orbit parameters are selected from of the TLE catalogue and calculated.The orbit determination and prediction accuracy of different space objects using SGP4/SDP4 model are given.The result shows that:the orbit determination accuracy of the near-earth objects is several hundred meters.The orbit determination accuracy of semi-synchronous orbit and geosynchronous orbit are 0.7 km and 1.9 km,respectively.The orbit determination accuracy of the elliptical orbit is related to the eccentricity.Except for few objects with eccentricities larger than 0.8,most errors of orbit determinations for elliptical orbit objects are less than 10km.Using SGP4/SDP4 model, errors are less than 40km for the following cases:predicting the near-earth objects for 3 days,the semi-synchronous orbit for 30 days,the geosynchronous orbit for 15 days and the elliptical orbit for 1 day.