A review of on-orbit life-time extension technologies for GEO satellites

With the reliability enhancement of on board elements and components, propellant-exhausition will become the main reason for retirement of geostationary satellites. The on-orbit life time extension technology is to launch life-time extension vehicle and dock with the retired satellite, and then prolong the life time of retired satellite by refuelling or assisted control. Statistics and analysis of retired geostationary satellites in recent years are carried out in this paper, and then the basic concept of the on-orbit life extension technique and task are introduced, after that, typical GEO life-time extension projects are investigated, moreover the advance of key technique, such as rendezvous orbit planning and control, vision based measurement and relative navigation are introduced respectively. The development of on-orbit life time extension technique will have great impact on design and operation in the future of GEO satellites.