GLONASS ambiguity resolution of mixed receiver types without external calibration


GLONASS processing from mixed receiver types is typically subject to unmodeled inter-frequency phase biases which prevent carrier phase ambiguity parameters from converging to integers. Receiver-dependent values have been proposed to mitigate the contribution of these biases, but are still subject to a number of issues, such as firmware updates. Recent studies have demonstrated that the origin of inter-frequency biases is a misalignment between phase and code observations, and could be calibrated to first order by manufacturers. In this contribution, a calibration-free method for GLONASS ambiguity resolution is presented in which ambiguities naturally converge to integers. A mandatory condition is that two GLONASS satellites with adjacent frequency numbers are observed simultaneously, although this condition can be relaxed once a fixed solution has been obtained. This approach then permits the integration of different receiver types and firmware versions into seamless processing.

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The authors would like to acknowledge the Geodetic Research Laboratory at UNB for sharing GNSS data from their continuously operating receivers. The reviewers of this paper are also acknowledged for their helpful suggestions in improving this manuscript. This paper is published under the auspices of the NRCan Earth Sciences Sector as contribution number 20120426.

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Correspondence to Simon Banville.

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Banville, S., Collins, P. & Lahaye, F. GLONASS ambiguity resolution of mixed receiver types without external calibration. GPS Solut 17, 275–282 (2013).

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  • Ambiguity resolution
  • Inter-frequency biases
  • Decoupled-clock model