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Performance of the BDS3 experimental satellite passive hydrogen maser

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Various types of onboard atomic clocks such as rubidium, cesium and hydrogen have different frequency accuracies and frequency drift rate characteristics. A passive hydrogen maser (PHM) has the advantage of low-frequency drift over a long period, which is suitable for long-term autonomous satellite time keeping. The third generation of Beidou Satellite Navigation System (BDS3) is equipped with PHMs which have been independently developed by China for their IGSO and MEO experimental satellites. Including Galileo, it is the second global satellite navigation system that uses PHM as a frequency standard for navigation signals. We briefly introduce the PHM design at the Shanghai Astronomical Observatory (SHAO) and detailed performance evaluation of in-orbit PHMs. Using the high-precision clock values obtained by satellite-ground and inter-satellite measurement and communication systems, we analyze the frequency stability, clock prediction accuracy and clock rate variation characteristics of the BDS3 experimental satellites. The results show that the in-orbit PHM frequency stability of the BDS3 is approximately 6 × 10−15 at 1-day intervals, which is better than those of other types of onboard atomic clocks. The BDS3 PHM 2-, 10-h and 7-day clock prediction precision values are 0.26, 0.4 and 2.2 ns, respectively, which are better than those of the BDS3 rubidium clock and most of the GPS Block IIF and Galileo clocks. The BDS3 PHM 15-day clock rate variation is − 1.83 × 10−14 s/s, which indicates an extremely small frequency drift. The 15-day long-term stability results show that the BDS3 PHM in-orbit stability is roughly the same as the ground performance test. The PHM is expected to provide a highly stable time and frequency standard in the autonomous navigation case.

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  • Allan DW (1987) Time and frequency (Time-Domain) characterization, estimation, and prediction of precision clocks and oscillators. IEEE Trans Ultrason Ferroelectr Freq Control (UFFC) 34(6):647–654.

    Article  Google Scholar 

  • Gong H, Ni S, Mou W, Zhu X, Wang F (2012). Estimation of COMPASS on-board clock short-term stability. In: Proceedings of European frequency and time forum (EFTF), pp 383–386

  • Gonzalez Martinez FJ (2014). Performance of new GNSS satellite clocks. Doctor Dissertation. KIT Scientific Publishing, Karlsruhe

  • Hackel S, Steigenberger P, Hugentobler U, Uhlemann M, Montenbruck O (2015) Galileo orbit determination using combined GNSS and SLR observations. GPS Solut 19(1):15–25.

    Article  Google Scholar 

  • Hauschild A, Montenbruck O, Steigenberger P (2013) Short-term analysis of GNSS clocks. GPS Solut 17(3):295–307

    Article  Google Scholar 

  • Liu L, Zhu L, Han C, Liu X, Li C (2009) The model of radio two-way time comparison between satellite and station and experimental analysis. Chin Astron Astrophys 33(4):431–439

    Article  Google Scholar 

  • Montenbruck O, Steigenberger P, Schönemann E, Hauschild A, Hugentobler U, Dach R, Becker M (2011). Flight characterization of new generation GNSS satellite clocks. In: Proceedings ION GNSS 2011, Institute of Navigation, Portland OR, USA, 21–23 September, pp 2959–2969

  • Montenbruck O, Hugentobler U, Dach R, Steigenberger P, Hauschild A (2012) Apparent clock variations of the Block IIF-1 (SVN62) GPS satellite. GPS Solut 16(3):303–313

    Article  Google Scholar 

  • Montenbruck O, Hauschild A, Steigenberger P, Hugentobler U, Teunissen P, Nakamura S (2013) Initial assessment of the COMPASS/BeiDou-2 regional navigation satellite system. GPS Solut 17(2):211–222.

    Article  Google Scholar 

  • Pan J, Hu X, Zhou S, Tang C, Guo R, Zhu L, Tang G, Hu G (2018) Time synchronization of new-generation BDS satellites using inter-satellite link measurements. Adv Space Res.

    Google Scholar 

  • Ren X, Yang Y, Zhu J, Xu T (2017) Orbit determination of the next-generation Beidou satellites with intersatellite link measurements and a priori orbit constraints. Space Res, Adv.

    Google Scholar 

  • Senior K (2010) SVN62 Clock Analysis using IGS Data, IGSMAIL-6218. Accessed 6 Aug 2010

  • Sesia I (2008) Estimating the Allan variance in the presence of long periods of missing data and outliers. Metrologia 45(6):134–142

    Article  Google Scholar 

  • Shuai T, Xie Y (2016) The onboard passive hydrogen maser for navigation satellite. SCIENCE 68(5):11–15 in Chinese

    Google Scholar 

  • Steigenberger P, Montenbruck O (2017) Galileo status: orbits, clocks, and positioning. GPS Solut 21(2):319–331.

    Article  Google Scholar 

  • Steigenberger P, Hugentobler U, Hauschild A, Montenbruck O (2013) Orbit and clock analysis of Compass GEO and IGSO satellites. J Geod 87(6):515–525

    Article  Google Scholar 

  • Svehla D (2010). Complete relativistic modelling of the GIOVE-B clock parameters and its impact on POD, track–track ambiguity resolution and precise timing. IGS Workshop 2010, Springer, Newcastle

  • Tang C, Hu X, Zhou S, Guo R, He F, Liu L, Zhu L, Li X, Wu S, Zhao G et al (2016) Improvement of orbit determination accuracy for Beidou navigation satellite system with two-way satellite time frequency transfer. Adv Space Res 58(7):1390–1400

    Article  Google Scholar 

  • Uhlemann M, Gendt G, Ramatschi M, Deng Z (2015) GFZ global Multi-GNSS network and data processing results. In: Rizos C, Willis P (eds) IAG 150 Years. International Association of Geodesy Symposia, vol 143. Springer, Cham.

  • Wang B, Lou Y, Liu J, Zhao Q, Su X (2015) Analysis of BDS satellite clocks in orbit. GPS Solut 20(4):783–794

    Article  Google Scholar 

  • Wang H, Xie J, Zhuang J, Wang Z (2017) Performance analysis and progress of inter-satellite-link of Beidou system. In: Proceedings of ION GNSS 2017, Portland OR, USA, 25–29 Sept, pp 1178–1185

  • Yang D, Yang J, Li G, Zhou Y, Tang C (2017) Globalization highlight: orbit determination using BeiDou inter-satellite ranging measurements. GPS Solut.

    Google Scholar 

  • Zhao Q, Wang C, Guo J, Wang B, Liu J (2018) Precise orbit and clock determination for BeiDou-3 experimental satellites with yaw attitude analysis. GPS Solut.

    Google Scholar 

  • Zhou S, Hu X, Wu B, Liu L, Qu W, Guo R, He F, Cao Y, Wu X, Zhu L et al (2011) Orbit determination and time synchronization for a GEO/IGSO satellite navigation constellation with regional tracking network. Sci China Phys Mech Astron 54:1089–1097

    Article  Google Scholar 

  • Zhou S, Cao Y, Zhou J, Hu X, Tang C, Liu L, Guo R, He F, Chen J, Wu B (2012) Positioning accuracy assessment for the 4GEO/5IGSO/2MEO constellation of COMPASS. Sci China Phys Mech Astron 55:2290–2299

    Article  Google Scholar 

  • Zhou S, Hu X, Liu L, Guo R, Zhu L, Chang Z, Tang C, Gong X, Li R, Yu Y (2016) Applications of two-way satellite time and frequency transfer in the BeiDou navigation satellite system. Sci China Phys Mech Astron 59:109511

    Article  Google Scholar 

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The IGS and GFZ are greatly acknowledged for providing the GNSS products. The authors are grateful for the comments and remarks of the reviewers and editors, which helped to improve the manuscript. This work was supported by the National key Research Program of China “Collaborative Precision Positioning Project” (Grant No. 2016YFB0501900), the National Natural Science Foundation of China (Grant No. 41574029), the Youth Innovation Promotion Association CAS (Grant No. 2016242) and Shanghai Science and Technology Committee Foundation (Grant No. 16511103003).

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Correspondence to Shanshi Zhou.

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Wu, Z., Zhou, S., Hu, X. et al. Performance of the BDS3 experimental satellite passive hydrogen maser. GPS Solut 22, 43 (2018).

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