Abstract
The Chinese BeiDou Navigation Satellite System (BDS) has completed its first milestone by providing coverage of the Asia–Pacific area navigation service since December 27, 2012. With the combination of BDS, the GNSS precise point positioning (PPP) can improve its positioning accuracy, availability and reliability. However, in order to achieve the best positioning solutions, the inter-system bias (ISB) between GPS and BDS must be resolved as precisely as possible. In this study, a 1-week period (GPS week 1810) of GPS/BDS observations for 18 distributed stations from the International GNSS Service Multi-GNSS Experiment are processed. Primarily, the ISB is estimated by an extended Kalman filter as a piece-wise parameter every 30 min. Then we generate a smoothed ISB series (ISB_s) with a sliding window median filter to reject the outliers from the original estimated ISB series (ISB_o). After analysing the characteristics of the ISB_s, a short-term station-dependent ISB model based on a 1-week period is proposed in this study. This model consists of a quadratic polynomial in time and two or three periodic functions with diurnal and semi-diurnal periods. Frequency spectrum analysis is used to determine the periods of the periodic functions, and the coefficients of the quadratic function and the periodic functions are estimated by least squares. For model verification, we compare the ISB derived from the model (ISB_m) with ISB_s (assumed the true values). The comparisons indicate an almost normal distribution. It is found that the proposed model is consistent with the true values: the root-mean-square (RMS) values being about 0.7 ns, and some stations are even better. This means that the short-term ISB model proposed has a high fitting accuracy. Hence, it can be used for ISB prediction. Comparing the prediction ISB series (ISB_p) with ISB_s in the following week (GPS week 1811), we can draw the conclusion that the accuracy of the prediction declines with an increase in the time period. The 1-day period precision can achieve 0.57–1.21 ns, while the accuracy of the 2-day prediction decreases to 0.77–1.72 ns. Hence, we recommend a predicting duration of 1 day. The proposed model will be beneficial for subsequent GPS/BDS PPP or precise orbit determination (POD) since the ISB derived from this model can be considered as a priori constraint in the PPP/POD solutions. With this a priori constraint, the convergence time can be shortened by 19.6, 16.1 and 2.4 % in N, E and U components, respectively. The accuracy of result in the E component is remarkably improved by 11.9 %.
Similar content being viewed by others
Explore related subjects
Discover the latest articles, news and stories from top researchers in related subjects.References
Bergland GD (1969) A guided tour of the fast fourier transform. IEEE Spectr 6(7):41–52. doi:10.1109/mspec.1969.5213896
Boehm J, Niell A, Tregoning P, Schuh H (2006) Global mapping function (GMF): a new empirical mapping function based on numerical weather model data. Geophys Res Lett. doi:10.1029/2005gl025546
Chen JP, Zhang YZ, Wang JG, Yang SN, Dong DA, Wang JX, Qu WJ, Wu B (2015) A simplified and unified model of multi-GNSS precise point positioning. Adv Space Res 55(1):125–134. doi:10.1016/j.asr.2014.10.002
Defraigne P, Bruyninx C, Guyennon N. (2007). GLONASS and GPS PPP for time and frequency transfer. In: Proceedings of the EFTF ‘07, Geneva, Switzerland
Duhamel P, Vetterli M (1990) Fast fourier-transforms—a tutorial review and a state-of-the-art. Sig Process 19(4):259–299. doi:10.1016/0165-1684(90)90158-U
Flohrer C (2008) Mutual validation of satellite-geodetic techniques and its impact on GNSS orbit modeling. Geodätisch-geophysikalische Arbeiten in der Schweiz, Vol 75
Ge M, Gendt G, Rothacher M, Shi C, Liu J (2008) Resolution of GPS carrier-phase ambiguities in precise point positioning (PPP) with daily observations. J Geodesy 82(7):389–399. doi:10.1007/s00190-007-0187-4
Geng JH, Shi C, Ge MR, Dodson AH, Lou YD, Zhao QL, Liu JN (2012) Improving the estimation of fractional-cycle biases for ambiguity resolution in precise point positioning. J Geodesy 86(8):579–589. doi:10.1007/s00190-011-0537-0
Hatch R (1982) The synergism of GPS code and carrier measurements. In: Proceedings of the third international symposium on satellite Doppler positioning at physical sciences laboratory of New Mexico State University, Feb. 8–12, Vol. 2, pp 1213–1231
Kouba J (2009) A guide to using International GNSS Service (IGS) Products. International GNSS Service (IGS)
Li M, Li WW, Shi C, Zhao QL, Su X, Qu LZ, Liu ZZ (2015a) Assessment of precipitable water vapor derived from ground-based BeiDou observations with Precise Point Positioning approach. Adv Space Res 55(1):150–162
Li X, Ge M, Dai X, Ren X, Fritsche M, Wickert J, Schuh H (2015b) Accuracy and reliability of multi-GNSS real-time precise positioning: GPS, GLONASS, BeiDou, and Galileo. J Geodesy 89(6):607–635. doi:10.1007/s00190-015-0802-8
Li X, Zhang X, Ren X, Fritsche M, Wickert J, Schuh H (2015c) Precise positioning with current multi-constellation global navigation satellite systems: GPS, GLONASS, Galileo and BeiDou. Sci Rep 5:8328. doi:10.1038/srep08328
Lu C, Li X, Nilsson T, Ning T, Heinkelmann R, Ge M, Glaser S, Schuh H (2015) Real-time retrieval of precipitable water vapor from GPS and BeiDou observations. J Geodesy. doi:10.1007/s00190-015-0818-0
Mann KA, Werner FW, Palmer AK (1989) Frequency spectrum analysis of wrist motion for activities of daily living. J Orthopaedic Res 7(2):304–306. doi:10.1002/jor.1100070219
Montenbruck O, Steigenberger P, Khachikyan R, Weber G, Langley RB, Mervart L, Hugentobler U (2013) IGS-MGEX: preparing the ground for multi-constellation GNSS science. In: 4th international colloquium on scientific and fundamental aspects of the Galileo system, 4–6 December 2013, Prague, CZ
Nadarajah N, Teunissen PJG, Raziq N (2013) BeiDou inter-satellite-type bias evaluation and calibration for mixed receiver attitude determination. Sensors-Basel 13(7):9435–9463
Nadarajah N, Teunissen PJG, Raziq N (2014) Instantaneous BeiDou-GPS attitude determination: a performance analysis. Adv Space Res 54(5):851–862
Odijk D, Teunissen PJG (2013) Characterization of between-receiver GPS-Galileo inter-system biases and their effect on mixed ambiguity resolution. GPS Solut 17(4):521–533. doi:10.1007/s10291-012-0298-0
Odolinski R, Teunissen PJG, Odijk D (2015a) Combined BDS, Galileo, QZSS and GPS single-frequency RTK. Gps Solut 19(1):151–163
Odolinski R, Teunissen PJG, Odijk D (2015b) Combined GPS plus BDS for short to long baseline RTK positioning. Meas Sci Technol 26(4):045801
Paziewski J, Wielgosz P (2015) Accounting for Galileo-GPS inter-system biases in precise satellite positioning. J Geodesy 89(1):81–93. doi:10.1007/s00190-014-0763-3
Petit G, Luzum B, IERS Conventions (2010). In: Proceedings of the IERS Technical Note 36. Verlag des Bundesamts für Kartographie und Geodäsie, Frankfurt am Main
Torre AD, Caporali A (2014) An analysis of intersystem biases for multi-GNSS positioning. Gps Solut 19(2):297–307. doi:10.1007/s10291-014-0388-2
Wang M, Cai HZ, Pan ZP (2015) BDS/GPS relative positioning for long baseline with undifferenced observations. Adv Space Res 55(1):113–124
Wanninger L (2012) Carrier-phase inter-frequency biases of GLONASS receivers. J Geodesy 86(2):139–148. doi:10.1007/s00190-011-0502-y
Wu J, Wu S, Hajj G, Bertiger W, Lichten S (1992) Effects of antenna orientation on GPS carrier phase. Astrodynamics 1:1647–1660
Yang Y, Song L, Xu T (2002) Robust estimator for correlated observations based on bifactor equivalent weights. J Geodesy 76(6–7):353–358. doi:10.1007/s00190-002-0256-7
Yang YX, Li JL, Xu JY, Tang J, Guo HR, He HB (2011) Contribution of the Compass satellite navigation system to global PNT users. Chin Sci Bull 56(26):2813–2819. doi:10.1007/s11434-011-4627-4
Zhao SH, Cui XW, Guan F, Lu MQ (2014) A Kalman filter-based short baseline RTK algorithm for single-frequency combination of GPS and BDS. Sensors-Basel 14(8):15415–15433
Zhou J (1989) Classical theory of errors and robust estimation. Acta Geodaetica Cartogr Sin 18(2):115–120
Acknowledgments
This study is supported by the Chinese Scholarship Council, Technical University of Berlin, German Research Centre for Geosciences Potsdam and Institute of Space Sciences of Shandong University. This work is supported by the National Natural Science Foundation of China (41574013, 41574025 and 41174008). The authors would like to thank IGS and MGEX for providing the GPS and BDS data. Thanks also go to three reviewers for their valuable comments which have improved this paper considerably.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Jiang, N., Xu, Y., Xu, T. et al. GPS/BDS short-term ISB modelling and prediction. GPS Solut 21, 163–175 (2017). https://doi.org/10.1007/s10291-015-0513-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10291-015-0513-x