Experiments and analyses are carried out for GEO and joint GEO/IGSO precise orbit determination using data recorded by China's regional tracking network.Results show that joint GEO/IGSO orbit determination effecti...Experiments and analyses are carried out for GEO and joint GEO/IGSO precise orbit determination using data recorded by China's regional tracking network.Results show that joint GEO/IGSO orbit determination effectively solves the problem of poor observation geometry for GEO satellites.The laser radial evaluation thus confirms that precision is as good as less than 0.1 m.In the case of joint orbit determination,solving the empirical acceleration can reduce errors introduced by the imprecise solar radiation pressure model used for Chinese satellites.This method also improves the accuracy of orbit prediction in the radial direction.The ephemeris accuracy is thus improved and the ephemeris can provide a better service to users with navigation and positioning requirements.展开更多
Solar sail is used to achieve a geocentric sun-synchronous frozen orbit.This kind of orbit combines the characteristics of both sun-synchronous orbits and frozen orbits.Furthermore,the impossible orbits for a typical ...Solar sail is used to achieve a geocentric sun-synchronous frozen orbit.This kind of orbit combines the characteristics of both sun-synchronous orbits and frozen orbits.Furthermore,the impossible orbits for a typical spacecraft such as sun-synchronous orbits whose inclination is less than 90° are also possible for solar sail.To achieve a sun-synchronous frozen orbit,the characteristic acceleration of the sail is chosen properly.In addition,the attitude of the sail is adjusted to keep the sun-synchronous and frozen characteristics.The perturbations including atmosphere drag,third-body gravitational forces and shaded regions are discussed,where the atmosphere drag is cancelled by solar radiation pressure force,third-body gravitational forces have negligible effects on the orbit and the shaded region can be avoided by choosing the classical orbit elements of the sail.At last,a numerical example is employed to validate the sun-synchronous frozen characteristics of the sail.展开更多
基金supported by the National Natural Science Foundation of China (Grant No.41074020)
文摘Experiments and analyses are carried out for GEO and joint GEO/IGSO precise orbit determination using data recorded by China's regional tracking network.Results show that joint GEO/IGSO orbit determination effectively solves the problem of poor observation geometry for GEO satellites.The laser radial evaluation thus confirms that precision is as good as less than 0.1 m.In the case of joint orbit determination,solving the empirical acceleration can reduce errors introduced by the imprecise solar radiation pressure model used for Chinese satellites.This method also improves the accuracy of orbit prediction in the radial direction.The ephemeris accuracy is thus improved and the ephemeris can provide a better service to users with navigation and positioning requirements.
基金supported by the National Natural Science Foundation of China (Grants Nos.10902056 and 10832004)State Key Lab of Astronautical Dynamics of China (Grant No. 2011ADL-DW0201)
文摘Solar sail is used to achieve a geocentric sun-synchronous frozen orbit.This kind of orbit combines the characteristics of both sun-synchronous orbits and frozen orbits.Furthermore,the impossible orbits for a typical spacecraft such as sun-synchronous orbits whose inclination is less than 90° are also possible for solar sail.To achieve a sun-synchronous frozen orbit,the characteristic acceleration of the sail is chosen properly.In addition,the attitude of the sail is adjusted to keep the sun-synchronous and frozen characteristics.The perturbations including atmosphere drag,third-body gravitational forces and shaded regions are discussed,where the atmosphere drag is cancelled by solar radiation pressure force,third-body gravitational forces have negligible effects on the orbit and the shaded region can be avoided by choosing the classical orbit elements of the sail.At last,a numerical example is employed to validate the sun-synchronous frozen characteristics of the sail.
