Algorithm Research And Realization Of GPS Cycle-slip Detection And Repair

In the high precision GPS positioning and navigation, detecting andrepairing for GPS cycle-slip is an important problem, which is necessary toresolve it. This thesis summarizes and analyses the theory and algorithms ofGPS carrier-phase cycle-slip detection and repair. Polynomial fitting,Ionospheric residual, Melbourne-Wübbena combination and triple-differenceare the mathematic basis of the theory and algorithms of GPS carrier-phasecycle-slip detection and correction in this paper. The procedures and thedetection effect of the approaches are accomplished and analyzed andverifiedwithsampledatasets.For Polynomial fitting, some relevant literatures only give thetheoretical analysis on the effect of sampling frequency. In this paper, theobservations of different sampling frequency are processed with 3 orderpolynomial, the test show that the detect capability of this method reducewiththedecreaseofsamplingfrequency.Hence,inpractice,itisnecessarytodetermine the extent of cycle slips according as the sampling frequency. Thetest for Melbourne-Wübbena combination which adopts the recursive algorithmshowthatitcandetect0.5cyclereliably.Forthefirsttime,theC/Acode pseudo-ranges are used to deal with the ambiguous problem inIonospheric residual method, the results verified this method can detect andrepair cycle slips effectively. When the loss of thesignal lock is not long, thetriple difference algorithm is an effective approach to detect and repair thecycle-slip.Here,thenon-interactivealgorithmisappliedtotestit.This paper introduced GPS modernization and the extra-wide-lanecombination and analyzed the model and procedure of this combination usedto determine the L1 and L2 ambiguity, and then improved the actualizingprocedure. The software based on this combination is developed, and thenverifiedtheeffectivenessofthismethod...