Abstract: ThecombinedobservationsanderrorsofBeidousatellitenavigationsystembasedontribanddoubledifferencewerediscussed.AnincrementaldistancecorrectionbasedfuzzyCMeansalgorithmwasproposedtoovercomethedisadvantageoftheclusteringmethod，whichpreviouslyusedtostudythecombinationobservationsofGPStribanddata.Thecorrectclassificationcanbegotbyadjustingthefactorandclustercenterofthesampledistancefromthecentereffectivelytoobtainareasonabledegreeofmembershipandavoiddeterminingthenumberofclustersofhumanirrationality.Thedistancebasedclusteringvalidityindexcorrectionwascreated,andtheoptimalnumberofclusterscanbeautomaticallyobtainedbyintroducinganincrementalwhenthedatawasincreasedbasedontheoriginaldataset.Thenewdatawereclassifiedbasedontheoriginaldatasetwithoutrecalculation.Thefeasibilityandreliabilitywereprovedbythematrixtransformationmethodandtypicalexamples.

Key words: FuzzyCMeans, Distancecorrection, Tribandcombination, Indicatorsofeffectiveness, Beidousatellitenavigationsystem