›› 2011, Vol. 31 ›› Issue (2): 9-15.doi: 10.3780/j.issn.1000-758X.2011.02.002

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Determination of the Ambiguity Search Space in Hybrid GPS/Galileo Navigation

ZHAO  Yi1,2, GONG  Cheng2, DENG  Ning3   

  • Received:2010-05-25 Revised:2010-08-30 Published:2011-04-25 Online:2011-04-25

Abstract: In order to fix the ambiguities in hybrid GPS/Galileo navigation and positioning, several conventional spacedetermining methods for least squares ambiguity decorrelation adjustment (LAMBDA) in GPS scenario were adopted in GPS/Galileo hybrid scenario. Simulation results show the conventional space-determining methods can′t meet the performance requirements for the high dimension in ambiguity vector. Compared to the conventional methods in determining LAMBDA ambiguity-search space, a new space-determining method specifically for high-dimension ambiguity vector was proposed. The simulation tests indicated that the proposed algorithm guaranteed an essential alignment of real and predefined candidate ambiguity numbers in joint  positioning mode, and hence improved the searching efficiency without scarifying success ratio in determining the phase ambiguity.

Key words: Integrated navigation, Ambiguity sapce determination , Least-squares ambiguity decorrelation adjustment , Simulation, Global positioning system , Galileo satellite system