GPS Solutions

, 23:7 | Cite as

Real-time carrier phase multipath detection based on dual-frequency C/N0 data

  • Zhetao Zhang
  • Bofeng LiEmail author
  • Yang Gao
  • Yunzhong Shen
Original Article


Since carrier phase multipath cannot be easily captured or mitigated, especially in real-time and kinematic applications, it is necessary to assess the multipath significance. We propose a real-time multipath detection method using dual-frequency carrier-to-noise-power-density ratio (C/N0). The proposed method takes full account of the relationship between the multipath and C/N0. Specifically, when the multipath effects are significant, the C/N0 behaviors not only deviate from the nominal values, but also differ in frequencies. Therefore, a combination test consisting of two statistics is developed. One is based on the C/N0 and the other is based on the differenced C/N0 between frequencies (∆C/N0). In addition, as an indispensable component of the multipath detection, a procedure for modeling the nominal C/N0 and ∆C/N0 functions is proposed. This procedure is based on a rigorous evaluation in terms of statistical properties. To validate the effectiveness of the proposed method, both static and kinematic experiments were carried out under environments with distinct levels of reflective and diffractive multipath. The results show that this method can effectively detect the multipath significance, and the two statistics are both indispensable. In addition, the modeling procedure improves the reliability of multipath detection with the minimal detectable multipath as small as 0.05 cycles, providing a great potential in high-precision applications.


Carrier phase Multipath detection C/N0 Real time 



This study is sponsored by the National Natural Science Foundation of China (41574023, 41622401, 41874030, and 41731069), the Scientific and Technological Innovation Plan from Shanghai Science and Technology Committee (18511101801) and the Fundamental Research Funds for the Central Universities. The first author acknowledges the support of the China Scholarship Council (CSC) for his visiting Ph.D. studies at the University of Calgary. The authors would like to acknowledge the editor and reviewers for the insightful and constructive comments, which improved the quality of the paper.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.College of Surveying and GeoInformaticsTongji UniversityShanghaiChina
  2. 2.Department of Geomatics EngineeringUniversity of CalgaryCalgaryCanada

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