Initial Results of the Precise Orbit Determination for the New-Generation BeiDou Satellites (BeiDou-3) Based on the iGMAS Network

Tan, Bingfeng; Yuan, Yunbin; Wen, Min; Ning, Yafei; Liu, Xifeng

doi:10.3390/ijgi5110196

Cited by 27 publications

(12 citation statements)

References 15 publications

(15 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Zhang et al presented an initial assessment of the new-generation signals and of the initial results of single epoch relative positioning [9]. Tan et al showed the initial results of the precise orbit determination with nine stations [10]. Xie et al evaluated the multipath effect and the performance of the precise orbit and clock determination [11].…”

Section: Introductionmentioning

confidence: 99%

Characteristics of BeiDou-3 Experimental Satellite Clocks

Geng

Zhao

et al. 2018

Remote Sensing

View full text Add to dashboard Cite

The characteristics of the improved Atomic Frequency Standard (AFS) operated on the latest BeiDou-3 experimental satellites are analyzed from day-of-year (DOY) 254 to 281, of the year 2017, considering the following three aspects: stability, periodicity, and prediction precision. The two-step method of Precise Orbit Determination (POD) is used to obtain the precise clock offsets. We presented the stability of such new clocks and studied the influence of the uneven distribution of the ground stations on the stability performance of the clock. The results show that the orbit influence on the Medium Earth Orbit (MEO) clock offsets is the largest of three satellite types, especially from 3 × 10 3 s to 8.64 × 10 4 s. Considering this orbit influence, the analysis shows that the Passive Hydrogen Maser (PHM) clock carried on C32 is approximately 2.6 × 10 − 14 at an interval of 10 4 , and has the best stability for any averaging intervals among the BeiDou satellite clocks, which currently achieves a level comparable to that of the PHM clock of Galileo, and the rubidium (Rb) clocks of Global Positioning System (GPS) Block IIF. The stability of the improved Rb AFS on BeiDou-3 is also superior to that of BeiDou-2 from 3 × 10 2 s to 3 × 10 3 s, and comparable to that of Rb AFS on the Galileo. Moreover, the periodicity of the PHM clock and the improved Rb clock are presented. For the PHM clock, the amplitudes are obviously reduced, while the new Rb clocks did not show a visible improvement, which will need further analysis in the future. As expected, the precision of the short-term clock prediction is improved because of the better characteristics of AFS. The Root Mean Square (RMS) of 1-h clock prediction is less than 0.16 ns.

show abstract

Section: Introductionmentioning

confidence: 99%

Characteristics of BeiDou-3 Experimental Satellite Clocks

Geng

Zhao

et al. 2018

Remote Sensing

View full text Add to dashboard Cite

show abstract

“…In Equation (9), the diagonal elements δ kk can be calculated by δ kk = STD k , which is the standard deviation of the fitting residuals for the k th satellite, and for the non-diagonal elements, e.g., for the k th satellite and j th satellite,δ k j = r k j δ kk • δ jj is the covariance between the k th and the j th satellites, in which r kj is the correlation coefficient between the two satellites of k th and the j th . r kj can be calculated by Equation (10), where m k denotes the mean of the clock offset series:…”

Section: Trend Term Modeling Of the Clock Offsetmentioning

confidence: 99%

“…In orbit determination, un-differenced ionosphere-free code and a phase combination of B1I and B3I observations were conducted. Moreover, the arc length is set to three-days, and a parameter configuration similar to [10,13] is used. It is noted that the un-differenced and double-differenced methods are two popular data processing strategies for orbit determination, and they each have their own advantages and disadvantages.…”

Section: Ultra-rapid Orbit Determination Based On Clock Offsets Constmentioning

confidence: 99%

“…For different navigation satellite systems, precise satellite orbit and clock offset products are still prerequisites in the domain of high-precision applications, especially for real-time or near real-time PNT services [5]. For BDS, research over BDS-2's orbit and clock offset has been mainly focused on the following three key aspects: (1) based on the available regional tracking network [6,7], the data processing strategies are constrained to a small number, and uneven geographical distribution, of ground tracking stations; (2) satellite geometric and physical models are refined [8][9][10], such as attitude models, sun radiation pressure, and the phase centre; (3) multi-GNSS observations are combined to augment BDS-2's performance. BDS-2's orbit determination has been studied extensively to improve accuracy and the relevant algorithms [11][12][13].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A BDS-2/BDS-3 Integrated Method for Ultra-Rapid Orbit Determination with the Aid of Precise Satellite Clock Offsets

Wang

Zhang

2019

Remote Sensing

View full text Add to dashboard Cite

The accuracy of ultra-rapid orbits is a key parameter for the performance of GNSS (Global Navigation Satellite System) real-time or near real-time precise positioning applications. The quality of the current BeiDou demonstration system (BDS) ultra-rapid orbits is lower than that of GPS, especially for the new generational BDS-3 satellites due to the fact that the availability of the number of ground tracking stations is limited, the geographic distribution of these stations is poor, and the data processing strategies adopted are not optimal. In this study, improved data processing strategies for the generation of ultra-rapid orbits of BDS-2/BDS-3 satellites are investigated. This includes both observed and predicted parts of the orbit. First, the predicted clock offsets are taken as constraints in the estimation process to reduce the number of the unknown parameters and improve the accuracy of the parameter estimates of the orbit. To obtain more accurate predicted clock offsets for the BDS’ orbit determination, a denoising method (also called the Tikhonov regularization algorithm), inter-satellite correlation, and the partial least squares method are all incorporated into the clock offsets prediction model. Then, the Akaike information criterion (AIC) is used to determine the arc length in the estimation models by taking the optimal arc length in the estimation of the initial orbit states into consideration. Finally, a number of experiments were conducted to evaluate the performance of the ultra-rapid orbits resulting from the proposed methods. Results showed that: (1) Compared with traditional models, the accuracy improvement of the predicted clock offsets from the proposed methods were 40.5% and 26.1% for BDS-2 and BDS-3, respectively; (2) the observed part of the orbits can be improved 9.2% and 5.0% for BDS-2 and BDS-3, respectively, by using the predicted clock offsets as constraints; (3) the accuracy of the predicted part of the orbits showed a high correlation with the AIC value, and the accuracy of the predicted orbits could be improved up to 82.2%. These results suggest that the approaches proposed in this study can significantly enhance the accuracy of the ultra-rapid orbits of BDS-2/BDS-3 satellites.

show abstract

“…Attributed to the project of International GNSS Monitoring and Assessment Service (iGMAS), there are over 10 stations that are capable for BDS-3 satellite tracking. Though the number of stations is rather limited, Tan et al (2016) presented the first attempt of precise orbit determination (POD) for the experimental satellites with the old B1, B2 and B3 signals. Xie et al (2017) presents the POD results with the new navigation signals, and the orbit overlap and the satellite laser ranging (SLR) evaluation both suggested that the POD precision is about 2-6 dm in 3D and 1-2 dm in the radial component.…”

Section: Introductionmentioning

confidence: 99%

BDS-3 differential code bias estimation with undifferenced uncombined model based on triple-frequency observation

Wang

Zhao

et al. 2020

J Geod

View full text Add to dashboard Cite

Since 2015, the new generation global BDS system, i.e., BDS-3, has started its development with five experimental satellites demonstration system and has announced its initial global service officially on December 27, 2018. Among the various characteristics to be analyzed for the new generation BDS satellites, the differential code bias (DCB) is of special attention since that it has a direct dependence on the new signals, i.e., B1C and B2a, and it is one of the most intricacy problems in the ionosphere sensing and positioning with multi-GNSS and multi-frequency observations. To take the full capability of the triplefrequency BDS signals, this paper proposed a new method for the DCB estimation in which the undifferenced uncombined observations are processed in PPP mode. In addition, with the intention to estimate all the unknowns, including the DCB, in a single filter, the DESIGN (deterministic plus stochastic ionosphere model for GNSS) method is applied for the ionospheric delay constrains in this method. In the formula derivation, special attention is given to the DCB and clock parameters due to different frequencies for B1I/B1C, etc. Then, the efficiency of the new method is assessed with observations of 23 iGMAS stations capable for BDS triple-frequency tracking and 21 IGS stations capable for GPS triple-frequency tracking during DOY 001 to 090, 2019. Moreover, the traditional DCB estimation method by employing the geometry-free (GF) combination with the ionospheric delay removed by global ionosphere map product is also performed for comparison purpose. The experimental results suggest that by using the undifferenced uncombined solution, rather than the GF combination, the BDS-2 DCB on B1IB2I and B1CB3I can be improved, especially for the MEO satellites. Regarding to the DLR products, the undifferenced uncombined DCB solution presents a RMS of 0.32 ns and 0.27 ns for B1IB2I and B1CB3I, respectively. Concerning the BDS-3 satellites DCB, it is GF combination that performs better by a factor of 12.7% and 15.2% for B1CB2a and B1CB3I, respectively. This is mainly due to the fact that the undifferenced uncombined DCB solution is sensitive to the limited precision of the BDS-3 orbit and clock. This conclusion is further confirmed by the improvement in the GPS DCB solution with the new method. Compared with the GF combination solution, the STD for daily repeatability improves from 0.088 to 0.061 ns and 0.119 to 0.090 ns for satellite on C1WC2W and C1WC5X, respectively, by using the undifferenced uncombined model.

show abstract

Initial Results of the Precise Orbit Determination for the New-Generation BeiDou Satellites (BeiDou-3) Based on the iGMAS Network

Cited by 27 publications

References 15 publications

Characteristics of BeiDou-3 Experimental Satellite Clocks

Characteristics of BeiDou-3 Experimental Satellite Clocks

A BDS-2/BDS-3 Integrated Method for Ultra-Rapid Orbit Determination with the Aid of Precise Satellite Clock Offsets

BDS-3 differential code bias estimation with undifferenced uncombined model based on triple-frequency observation

Contact Info

Product

Resources

About