GPS Solutions

, Volume 17, Issue 4, pp 535–548 | Cite as

The ratio test for future GNSS ambiguity resolution

  • Sandra VerhagenEmail author
  • Peter J. G. Teunissen
Original Article


The performance of the popular ambiguity ratio test is analyzed. Based on experimental and simulated data, it is demonstrated that the current usage of the ratio test with fixed critical value is not sustainable in light of the enhanced variability that future global navigation satellite system (GNSS) ambiguity resolution will bring. As its replacement, the model-driven ratio test with fixed failure rate is proposed. The characteristics of this fixed-failure rate ratio test are described, and a performance analysis is given. The relation between its critical value and various GNSS model parameters is also studied. Finally, a procedure is presented for the creation of fixed failure rate look-up tables for the critical values of the ratio test.


Integer ambiguity resolution Ratio test Fixed failure rate Integer aperture estimation GNSS 



Peter Teunissen is Federation Fellow of the Australian Research Council (project FF0883188). The research of Sandra Verhagen is supported by the Dutch Technology Foundation STW, applied science division of NWO and the Technology Program of the Ministry of Economic Affairs. Part of this work was done in the framework of the project ‘New Carrier Phase Processing Strategies for Next Generation GNSS Positioning’ of the Cooperative Research Centre for Spatial Information (CRC-SI2). All this support is gratefully acknowledged.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.Delft University of TechnologyDelftThe Netherlands
  2. 2.Curtin UniversityPerthAustralia

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