Station-keeping Maneuver Monitoring and Moving-window Ground Track Fitting of GEO Satellites

The true firing period of station-keeping maneuver,if detected rapidly and reliably,can reduce effectively the unavailable time of GEO satellites among the navigation constellation.Based on the movement characteristics of the sub-satellite point(SSP)of GEOs,a 7-parameter fitting set was proposed including GEO elements and a mean drift acceleration of longitude.The fitting feasibility was validated for 10minutesSSP motion of GEOs.And then both the fitted semi-major series and RMS series of fit-predicting range residuals were utilized to jointly monitor the firing window in real time according to the principle and strategy of east-west maneuver.Using C-band range tracking data with on-board transponder of 1d,the moving-window kinematic fitting with a 20-min maneuver involved was applied.The results show that the proposed maneuver monitoring method is valid and sensible.