Method of collocating two Chinese geostationary satellites with two eccentricity vectors

Having failed to find any detailed technical information in the open literature concerning collocating two geostationary satellites with two eccentricity vectors, we have to do research and development ourselves to develop such information. We now present our engineering method of doing such collocation. A Chinese geostationary satellite was launched in 2003 and we brought another geostationary satellite previously launched to collocate in the same orbital position with the one launched in 2003 without collision and mutual interference. This collocation was successfully completed by using the principle involving two eccentricity vectors. In the full paper, we describe our engineering method in detail; in this abstract, we just list the three things we do in the full paper: (1) we explain the principles and method of multi-satellite collocation, taking into account the status of the satellites, the Chinese ground TT&C (Tracking, Telemetry and Command) system and the operation cost; (2) we explain the method of collocating several satellites by use of different eccentricity vectors; (3) we explain eccentricity vector control strategy in west/east maneuver and north/south maneuver. When the geostationary satellite launched in 2003 and another launched earlier was finally collocated in the same orbital position, our engineering method succeeded in keeping these two satellites at least 15 km apart when they were nearest.