Real-time carrier phase multipath detection based on dual-frequency C/N0 data
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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.
KeywordsCarrier 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.
- Bilich A, Larson K (2007) Mapping the GPS multipath environment using the signal-to-noise ratio (SNR). Radio Sci 42(6)Google Scholar
- Byun S, Hajj G, Young L (2002) Development and application of GPS signal multipath simulator. Radio Sci 37(6)Google Scholar
- Choi K, Bilich A, Larson K, Axelrad P (2004) Modified sidereal filtering: Implications for high-rate GPS positioning. Geophys Res Lett 31(22)Google Scholar
- Groves P, Jiang Z, Rudi M, Strode P (2013) A portfolio approach to NLOS and multipath mitigation in dense urban areas. Proc. ION GNSS 2013, Institute of Navigation, Nashville, Tennessee, USA, September 16–20, 3231–3247Google Scholar
- Hofmann-Wellenhof B, Lichtenegger H, Wasle E (2007) GNSS-global navigation satellite systems: GPS, GLONASS, Galileo, and more. Springer, New YorkGoogle Scholar
- Lehmann E, Romano J (2006) Testing statistical hypotheses. Springer, BerlinGoogle Scholar
- Phan Q, Tan S, Mcloughlin I (2013) GPS multipath mitigation: a nonlinear regression approach. GPS Solut 17(3):371–380Google Scholar
- Rost C, Wanninger L (2009) Carrier phase multipath mitigation based on GNSS signal quality measurements. J Appl Geod 3(2):81–87Google Scholar
- Serrano L (2013) Carrier-phase multipath mitigation in RTK-based GNSS dual-antenna systems. Dissertation, University of New BrunswickGoogle Scholar
- Tatarnikov D, Astakhov A (2014) Approaching millimeter accuracy of GNSS positioning in real time with large impedance ground plane antennas. Proc. ION ITM 2014, Institute of Navigation, San Diego, California, USA January 27–29, 844–848Google Scholar