Research On BeiDou Satellite Solar Radiation Pressure Model Refinement And It's Application In Autonomous Navigation Support System

Compared with BDS-2,BDS-3 satellite constellation is firstly equipped with the inter-satellite link which realized the precise distance measurement and communication among satellites as well as monitoring overseas satellite and uploading to make up the defect that it is difficult to lay out monitoring stations evenly and globally.Autonomous navigation utilized inter-satellite link measurement data to correct the long-term prediction reference orbit uploaded from the ground and completed the autonomous updating of down navigation message as well as maintained that the accuracy of navigation ephemeris will not decrease obviously in a certain time,which can make satellite navigation system continuously run for some time without depending on the ground operation control information.The autonomous navigation support system operated and controlled on the ground supplied BDS-3 with long-term and high-precision prediction orbit as the reference orbit of autonomous navigation.Therefore,the long-term prediction precision of the reference orbit is significant for the autonomous navigation running.The error of the reference orbit is mainly from the model error of the satellite perturbative force model.Except gravity,solar and lunar attraction,solar radiation pressure,the biggest perturbative force affecting navigation satellites and the biggest error source of perturbative force modeling,is related to satellite attitude,superficial area,materials and property.Basing on how to enhance the precision of the long-term prediction reference orbit,this article will study parameter variation characteristics of the solar radiation pressure model and establish the solar radiation pressure parameter long-term prediction model of the navigation satellite as well as increase the prediction precision of the long-term reference orbit to provide the satellite autonomous navigation with a precise reference standard.The main work of this thesis is as follows:1.It summarized existing typical solar radiation pressure models in detail and analyzed their merit and demerit.It obtained the short-term solar radiation pressure parameter via orbital dynamics parameter fitting and discovered that it can predict the cycle repetition feature.2.Through studying the prediction error of the orbital plane orientation parameter profoundly from qualitative and quantitative aspects,it discovered that the solar radiation pressure is the biggest perturbative force that affected the prediction precision of the orbital plane orientation parameter.3.The solar radiation pressure parameters of MEO/IGSO satellite have the periodic term with obvious annual variety in the direction of DO as well as the solar radiation pressure change following a half-year cycle in the direction of Y0.B0,the solar radiation pressure model parameter of MEO/IGSO satellite,is hardly periodic and generally fluctuating around 0,so the average of the solar radiation pressure parameter can be taken directly.The periodicity of the solar radiation pressure model parameters BS and BC of MEO satellite are relatively week while those two solar radiation pressure parameters of IGSO have more obvious periodic term with annual variety.According to the cycle repetition features of the short-term solar radiation pressure parameter,it used the Fourier series to fit the short-term solar radiation pressure parameter for three times and presented the refining method of navigation satellite solar radiation pressure models to establish long-term solar radiation pressure models.4.According to the established long-term solar radiation pressure model,it designed 3 calculating examples.Via analyzing the long-term prediction precision of the orbital plane orientation parameter,it verified the refining effect of the long-term solar radiation pressure model.Taking the long-term solar radiation pressure modeling approach presented in this article to predict the solar radiation pressure parameter,the prediction precision of the orbital plane orientation parameter in the 60-day arc is higher than the calculating example 2(taking the average of the solar radiation pressure parameters in 3 years)and IGSO satellite is more distinct.The prediction precision of the orbital plane orientation parameter of the calculating example 3(7-day precise ephemeris fitting)is much lower than the first two calculating examples in 60-day arc and the normal direction precision declines faster over time.Meanwhile,because of the high precise ephemeris of MEO satellite,the 60-day normal direction prediction precision of MEO satellite is higher than that of IGSO satellite in the 3 calculating examples.