Abstract: Abstract：For noncooperative objectives, with limited measuring method, only angle measurement information can be achieved for the midlong distance satellites. The lineofsightmeasurement relative navigation algorithm has low precision and observability for GEO satellites. Based on the combination of lineofsight intersatellitemeasurement and orbit forecast information of groundmeasurement, a method of relative navigation algorithm for GEO noncooperative satellites is presented. The system state equation based on the intersatellite relative motion model is established. The measurement equation is established based on LOS and orbit forecast information. EKF(extended Kalman filter) and UKF(unscented Kalman filter) methods are adopted. The effects of orbit forecast information measurement accuracy and filtering methods on the navigation accuracy are illuminated via the simulation and analysis.

Key words: Keywords：relative navigation, lineofsightmeasurement, extended Kalman filter, unscented Kalman filter