Improved tracklet association method for initial orbit determination of space debris

The initial orbital state of a space object cannot be determined using atracklet as the tracklet only contains angular and angular rate observations without any ranging information.One approach to determine confident initial orbits is to constructan admissible region,which restricts the range/range-rate to a compact subset by considering physical constraints.The initial orbit can subsequently be determined using atracklet association approach that correlatesall possible orbits derived from two tracklets.In this study,an improved tracklet association approach is proposed,which requiring a much smaller number of correlations by assigning a unique identification to each of the possible orbits derived from the same tracklet.The new approach is tested using two simulated tracklets from a GEO objectand the results indicate that the processing efficiency has been improved by the new approach.