The Research On The Theory Of Robust Determination Of Spacecraft Precision Orbit And Its Application

The orbit accuracy of the spacecrall is rNuired to be higher with thedevelopment of sPace technology. But the gross errors are incvitably exiSting in theobservations of the spacecraft tha are difficult to be all removed by the pre-process.Classical grOss error detechon and thentification is no pedectiy reliable sometiIns.The gross error will cut dOwn the accuray of orbit detennination which is estdriatedby classical least sWs because it is pooriy resistal to the effect of gross ermrs.Wdri high robustness, robust estimation can reduce sufficientiy or e1iminate the effectof gross ermrs on the estimate of parameters by choosing proper aPProaches so as toobtaln the best estimate in the presence of grOss ermrs as almost the same as the resultderived from regular observations. Although it has been widely used in many fields,but theory models, algorithm and aPPlicability need to be investigated When it isaPplied to detenninaion of the sPacecrall orbit.The robust batCh processor and its comPtalion stePs are set uP fordeterminaion of the spacecraft orbit. Givens-Gelltleman orthogonal transformationalgOrithm is aPPlied to it with the resolution of equlvaient weights discussed, and withthe numerical stability analyZed. The formulas are derived for posterior root meanW error and covariance matrix,'M-LS robuSt filtering, stat6 noise comPensation M-LS robust filtering,adaPtively M-LS robust filtCring, LS-M robust filtering and M-M robust filtering isstUdied for robust detenninaion of spacecraft orbit hased on discussion of classicalKalman filtering, stae noise comPensation algorithm filtering and adaPtivc1y filtering.The equlvalcn quasi-covariance matrix is proPOsed in robust filtering.The introdution of the equivalent weigh thechon and equivalen quasi-covariance Inatrix makes it possible for robust batch proeessor and robust filtering toaPply to orbit determination. Not only the models and algorithIns in mathematicalform but a1so the well-developed softwar fOr orbit determinaion can remain whenthe algorithIns of equivalent weigh funtion and equivalent quasi-covariance matrixare aPplied in robuSt determinaion of orbit.Some problems on GPS chased orbit determination in real-time are discussed.Thny are precision of GPS broadcaSt ePhemeris and its gross errors, geometric orbitdetermination, dynamic orbit determination, synthticaily geometric-dynamic orbitdeterminaion with the observations of pseudO-range and pseudO-range rate of singlefrequancylIAll kinds of orbit determination methods discussed in the paper are computed and compared with the laser range observations of satellite Lageos and GPS-based quasi-simulative, quasi-real observations, which verifies the robustness and efficiency of robust orbit determination.The orbit determination of the lunar probe is discussed, which is applicable research. First the GPS navigation of the lunar probe in the close earth orbit phase is analyzed. Then based on the ground tracking sites, choice of tracking type, distribution of Ground Tracking Site, adjustment of the guiding time, and accuracy of navigation of the lunar probe are investigated. The method and result of the research deserve reference to the practical engineering of lunar probe.