Started 1996, ongoing
Summary
Ambiguity validation tests include the acceptance test and discrimination test, which are both important steps in the GPS and GLONASS ambiguity resolution process. This study proposes an ambiguity discrimination test procedure based on a test statistic which is constructed by the difference (not the ratio as used in current procedures) between the minimum and second minimum quadratic form of the residuals in ambiguity identification, and its standard deviation. The distribution function of the proposed test statistic is theoretically identified as a standard normal distribution when the known a priori variance factor is used, or a Student's t distribution when the estimated variance factor is used. With this procedure, the ambiguity discrimination test is based on a more rigorous test statistic whose critical value can be calculated with any chosen level of significance.
Results
The proposed ambiguity validation testing procedures have been tested using GPS and GLONASS data sets from both static and kinematic positioning. Test results indicate that the proposed ambiguity discrimination test procedure is reliable for use in GPS and GLONASS ambiguity resolution.
References
Wang J (1999) Modelling and quality control for precise GPS and GLONASS satellite positioning. Ph.D thesis, School of Spatial Sciences, Curtin University, 171pp.
Wang J (1999) Separability of linear models and its applications in geodesy. Poster presentation at the 22nd IUGG General Assembly of the IUGG, Birmingham, July. (Abstract, Vol.A, p.439).
Wang J, Stewart M and Tsakiri M (1999) A comparative study of the integer ambiguity validation procedures. Proceedings of GPS'99, Tsukuba, Japan, October 18-22. (in press).
Wang J, Stewart M and Tsakiri M (1998) A discrimination test procedure for ambiguity resolution on-the-fly. Journal of Geodesy, 72: 644-653.
Wang J, Stewart M and Tsakiri M (1997) A new validation test procedure for ambiguity resolution On-The-Fly. Proceedings of KIS'97, Banff, Canada, June 3-6, pp. 279-287.
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