A METHOD TO CORRECT CATALOG ORBIT DETERMINATION VELOCITY ¹⁾

For the utilization space activities, the number of man-made space objects increases fast. Due to the limitation of the detect resource, the detected data of the mass space objects are less than what is adequate, which means a worse accuracy of the orbital calculated result. In this paper, the space objects are classified by the orbit altitude, and the influence on different perturbation factors are analyzed. It is indicated that with the perturbation model,the error of the atmospheric drag and the velocity of the initial radial direction is the major cause of the orbit propagation error, which is distributed along the track. By ignoring the error of the initial position, the values before and after the perturbation error caused by the orbit initial position error are approximately symmetric, which is confirmed in the simulation experiment. A method is then proposed to correct the catalog orbit determination velocity by reducing the position error propagated before the given point to improve the position precision propagated after the given point. In the experiment with the real observation data, the method works effectively in modifying the orbital result within the sparse data of the near-circular space object, and the accuracy of the self-catalogue space object is improved. The method improves the ability of the catalogue managing the space object.