scholarly journals Orbit Estimation of GEO-missions Applicable to NavIC Data

2020 ◽  
Vol 9 (4) ◽  
pp. 253-256
Keyword(s):  
Least Squares ◽  
Satellite Orbit ◽  
Satellite System ◽  
Global Navigation Satellite Systems ◽  
Satellite Orbits ◽  
Navigation Satellite ◽  
Initial State ◽  
Satellite Systems ◽  
Dc Algorithm ◽  
Orbit Estimation

Indian Regional Navigation Satellite System (IRNSS) is India’s own navigation system. It is a seven satellite constellation with the operational name NavIC – Navigation with Indian Constellation. Satellite Orbit determination (OD) estimates the position and velocity of orbiting satellite. The two main estimation algorithms widely used in Global Navigation Satellite Systems (GNSS) are Extended Kalman Filter (EKF) and Least Squares. This study on Batch Least Squares (BLS) - Differential Correction (DC) algorithm demonstrates precise orbit estimation of any GEO missions using only range measurements with crude initial state parameters. Currently, the study is based on simulated inputs and the satellite orbits are successfully estimated with position error in sub-centimeters level. Further, the work will be extended to live data of IRNSS satellites.

scholarly journals Satellite Navigation for Digital Earth

2019 ◽  
pp. 125-160
Author(s):  
Chuang Shi ◽  
Na Wei
Keyword(s):  
Satellite Orbit ◽  
Satellite System ◽  
Location Based Services ◽  
Global Navigation Satellite Systems ◽  
System Structure ◽  
Navigation Satellite ◽  
Satellite Systems ◽  
Digital Earth ◽  
Wide Area Augmentation System ◽  
Global Navigation Satellite

Abstract Global navigation satellite systems (GNSSs) have been widely used in navigation, positioning, and timing. China’s BeiDou Navigation Satellite System (BDS) would reach full operational capability with 24 Medium Earth Orbit (MEO), 3 Geosynchronous Equatorial Orbit (GEO) and 3 Inclined Geosynchronous Satellite Orbit (IGSO) satellites by 2020 and would be an important technology for the construction of Digital Earth. This chapter overviews the system structure, signals and service performance of BDS, Global Positioning System (GPS), Navigatsionnaya Sputnikovaya Sistema (GLONASS) and Galileo Navigation Satellite System (Galileo) system. Using a single GNSS, positions with an error of ~ 10 m can be obtained. To enhance the positioning accuracy, various differential techniques have been developed, and GNSS augmentation systems have been established. The typical augmentation systems, e.g., the Wide Area Augmentation System (WAAS), the European Geostationary Navigation Overlay Service (EGNOS), the global differential GPS (GDGPS) system, are introduced in detail. The applications of GNSS technology and augmentation systems for space-time geodetic datum, high-precision positioning and location-based services (LBS) are summarized, providing a reference for GNSS engineers and users.

scholarly journals Assessment of BeiDou differential code bias variations from multi-GNSS network observations

2016 ◽  
Vol 34 (2) ◽  
pp. 259-269 ◽  
Author(s):  
S. G. Jin ◽  
R. Jin ◽  
D. Li
Keyword(s):  
Orbital Plane ◽  
Satellite Orbit ◽  
Satellite System ◽  
Global Navigation Satellite Systems ◽  
Dominant Factor ◽  
Earth Orbit ◽  
Navigation Satellite ◽  
Differential Code Bias ◽  
Code Bias ◽  
Gnss Network

Abstract. The differential code bias (DCB) of global navigation satellite systems (GNSSs) affects precise ionospheric modeling and applications. In this paper, daily DCBs of the BeiDou Navigation Satellite System (BDS) are estimated and investigated from 2-year multi-GNSS network observations (2013–2014) based on global ionospheric maps (GIMs) from the Center for Orbit Determination in Europe (CODE), which are compared with Global Positioning System (GPS) results. The DCB of BDS satellites is a little less stable than GPS solutions, especially for geostationary Earth orbit (GEO) satellites. The BDS GEO observations decrease the precision of inclined geosynchronous satellite orbit (IGSO) and medium Earth orbit (MEO) DCB estimations. The RMS of BDS satellites DCB decreases to about 0.2 ns when we remove BDS GEO observations. Zero-mean condition effects are not the dominant factor for the higher RMS of BDS satellites DCB. Although there are no obvious secular variations in the DCB time series, sub-nanosecond variations are visible for both BDS and GPS satellites DCBs during 2013–2014. For satellites in the same orbital plane, their DCB variations have similar characteristics. In addition, variations in receivers DCB in the same region are found with a similar pattern between BDS and GPS. These variations in both GPS and BDS DCBs are mainly related to the estimated error from ionospheric variability, while the BDS DCB intrinsic variation is in sub-nanoseconds.

An Advanced Receiver Autonomous Integrity Monitoring (ARAIM) Ground Monitor Design to Estimate Satellite Orbits and Clocks

2020 ◽  
Vol 73 (5) ◽  
pp. 1087-1105
Author(s):  
Yawei Zhai ◽  
Jaymin Patel ◽  
Xingqun Zhan ◽  
Mathieu Joerger ◽  
Boris Pervan
Keyword(s):  
Measurement Errors ◽  
Satellite Orbit ◽  
Global Navigation Satellite Systems ◽  
Estimation Accuracy ◽  
Satellite Orbits ◽  
Integrity Monitoring ◽  
Satellite Systems ◽  
Receiver Autonomous Integrity Monitoring ◽  
The Impact ◽  
Advanced Receiver

This paper describes a method to determine global navigation satellite systems (GNSS) satellite orbits and clocks for advanced receiver autonomous integrity monitoring (ARAIM). The orbit and clock estimates will be used as a reference truth to monitor signal-in-space integrity parameters of the ARAIM integrity support message (ISM). Unlike publicly available orbit and clock products, which aim to maximise estimation accuracy, a straightforward and transparent approach is employed to facilitate integrity evaluation. The proposed monitor is comprised of a worldwide network of sparsely distributed reference stations and will employ parametric satellite orbit models. Two separate analyses, covariance analysis and model fidelity evaluation, are carried out to assess the impact of measurement errors and orbit model uncertainty on the estimated orbits and clocks, respectively. The results indicate that a standard deviation of 30 cm can be achieved for the estimated orbit/clock error, which is adequate for ISM validation.

scholarly journals Code Single Point Positioning Using Nominal Gnss Constellations (Future Perception)

2007 ◽  
Vol 42 (3) ◽  
pp. 149-153
Author(s):  
A. Farah
Keyword(s):  
Single Point ◽  
Satellite System ◽  
Global Navigation Satellite Systems ◽  
Navigation Satellite ◽  
Satellite Systems ◽  
Performance Improvements ◽  
Single Point Positioning ◽  
Global Navigation ◽  
Point Positioning ◽  
Global Navigation Satellite

Code Single Point Positioning Using Nominal Gnss Constellations (Future Perception) Global Navigation Satellite Systems (GNSS) have an endless number of applications in industry, science, military, transportation and recreation & sports. Two systems are currently in operation namely GPS (the USA Global Positioning System) and GLONASS (the Russian GLObal NAvigation Satellite System), and a third is planned, the European satellite navigation system GALILEO. The potential performance improvements achievable through combining these systems could be significant and expectations are high. The need is inevitable to explore the future of positioning from different nominal constellations. In this research paper, Bernese 5.0 software could be modified to simulate and process GNSS observations from three different constellations (GPS, Glonass and Galileo) using different combinations. This study presents results of code single point positioning for five stations using the three constellations and different combinations.

scholarly journals OBSERVATIONS OF SPACE DEBRIS IN THE VICINITY OF ORBITS OF GLOBAL NAVIGATION SATELLITE SYSTEMS

2020 ◽  
Vol 6 (3) ◽  
pp. 115-123
Author(s):  
Ivan Korobtsev ◽  
Tatyana Tsukker ◽  
Marina Mishina ◽  
Vladimir Goryashin ◽  
Maxim Eselevich
Keyword(s):  
Space Debris ◽  
Satellite System ◽  
Global Navigation Satellite Systems ◽  
Optical Measurements ◽  
Navigation Satellite ◽  
Satellite Systems ◽  
Orbital Parameters ◽  
Space Objects ◽  
Global Navigation ◽  
Global Navigation Satellite

The problem of the amount and characteristics of space debris in the vicinity of orbits of Global Navigation Satellite Systems (GNSS) is of significant interest from the viewpoint of safe operation of these systems. Attempts have repeatedly been made to search for space debris fragments in a given region of orbits, but have not led to cataloging such objects. Only in 2018, eight space objects were discovered which were not related to active or inactive spacecraft or their launch elements. Photometrical and trajectory observations with optical telescopes are practically the only source of information about characteristics of such objects. The paper presents a summary of the design features and technical characteristics of the new AZT-33VM telescope. We describe a technique for determining orbital parameters of non-cataloged space debris from optical measurements. We report the results of photometric observations of a space object, detected in the vicinity of orbits of the Global Navigation Satellite System GLONASS.

scholarly journals Satellite Availability and Service Performance Evaluation for Next-Generation GNSS, RNSS and LEO Augmentation Constellation

2021 ◽  
Vol 13 (18) ◽  
pp. 3698
Author(s):  
Haomeng Cui ◽  
Shoujian Zhang
Keyword(s):  
Satellite System ◽  
Low Earth Orbit ◽  
Global Navigation Satellite Systems ◽  
Navigation Satellite ◽  
Next Generation ◽  
Satellite Systems ◽  
Satellite Visibility ◽  
Under Construction ◽  
Global Navigation Satellite ◽  
Average Position

Positioning accuracy is affected by the combined effect of user range errors and the geometric distribution of satellites. Dilution of precision (DOP) is defined as the geometric strength of visible satellites. DOP is calculated based on the satellite broadcast or precise ephemerides. However, because the modernization program of next-generation navigation satellite systems is still under construction, there is a lack of real ephemerides to assess the performance of next-generation constellations. Without requiring real ephemerides, we describe a method to estimate satellite visibility and DOP. The improvement of four next-generation Global Navigation Satellite Systems (four-GNSS-NG), compared to the navigation constellations that are currently in operation (four-GNSS), is statistically analyzed. The augmentation of the full constellation the Quasi-Zenith Satellite System (7-QZSS) and the Navigation with Indian Constellation (11-NavIC) for regional users and the low Earth orbit (LEO) constellation enhancing four-GNSS performance are also analyzed based on this method. The results indicate that the average number visible satellites of the four-GNSS-NG will reach 44.86, and the average geometry DOP (GDOP) will be 1.19, which is an improvement of 17.3% and 7.8%, respectively. With the augmentation of the 120-satellite mixed-orbit LEO constellation, the multi-GNSS visible satellites will increase by 5 to 8 at all latitudes, while the GDOP will be reduced by 6.2% on average. Adding 7-QZSS and 11-NavIC to the four-GNSS-NG, 37.51 to 71.58 satellites are available on global scales. The average position DOP (PDOP), horizontal DOP (HDOP), vertical DOP (VDOP), and time DOP (TDOP) are reduced to 0.82, 0.46, 0.67 and 0.44, respectively.

scholarly journals ANALYSIS OF POSITIONING DEVIATION BETWEEN BEIDOU AND GPS BASED ON NATIONAL REFERENCE STATIONS IN CHINA

2021 ◽  
Vol XLIII-B1-2021 ◽  
pp. 209-214
Author(s):  
M. Chen ◽  
Q. Zhang
Keyword(s):  
Satellite System ◽  
Global Navigation Satellite Systems ◽  
Global Coordinate System ◽  
Gps Data ◽  
Observation Data ◽  
Navigation Satellite ◽  
Satellite Systems ◽  
National Reference ◽  
The North ◽  
Processing Modes

Abstract. In order to probe into the characteristics of positioning deviation between Beidou Navigation Satellite System (Beidou) and global positioning system (GPS), and investigate possible contribution of Beidou data to refinement of global coordinate system, refined calculation is made on observation data of 240 national reference stations that are distributed uniformly across China on the whole in this study. These stations support satellite signals of four global navigation satellite systems, including Beidou, GPS, GLONASS and Galileo, and a 5-year time span from 2016 to 2020 is adopted. In this study, PPP is calculated based on GPS data and Beidou single system data in no-difference resolution network mode, and accurate coordinates of national reference stations in two processing modes are obtained. Analysis of difference between the calculations based on Beidou data and on GPS data shows that the consistency between Beidou and GPS positioning results reaches about 5 mm in the east and in the north, and about 1.3 cm in the height direction.

Double-Difference Carrier-Phase Network Solution Using Nominal Gnss Constellations (Future Perception)

2008 ◽  
Vol 43 (2) ◽  
pp. 65-73
Author(s):  
A. Farah
Keyword(s):  
Carrier Phase ◽  
Satellite System ◽  
Global Navigation Satellite Systems ◽  
Double Difference ◽  
Navigation Satellite ◽  
Network Solution ◽  
Satellite Systems ◽  
Performance Improvements ◽  
Global Navigation ◽  
Global Navigation Satellite

Double-Difference Carrier-Phase Network Solution Using Nominal Gnss Constellations (Future Perception)Global Navigation Satellite Systems (GNSS) have an endless number of applications in industry, science, military, transportation and recreation & sports. Two systems are currently in operation namely GPS (the USA Global Positioning System) and GLONASS (the Russian GLObal NAvigation Satellite System), and a third is planned, the European satellite navigation system GALILEO. The potential performance improvements achievable through combining these systems could be significant and expectations are high. The need is inevitable to explore the future of positioning accuracy using different nominal constellations. In this research paper, Bernese 5.0 software could be modified to simulate and process GNSS observations from three different constellations (GPS, Glonass and Galileo) using different combinations. This study presents results of double-difference carrier-phase solution for five stations-network using the three constellations and different combinations.

scholarly journals Epoch-by-epoch estimation and analysis of BDS receiver differential code biases with the additional BDS-3 observations

2020 ◽  
Author(s):  
Qisheng Wang ◽  
Shuanggen Jin ◽  
Youjian Hu
Keyword(s):  
Satellite System ◽  
Global Navigation Satellite Systems ◽  
Navigation Satellite ◽  
Satellite Systems ◽  
Code Bias ◽  
Space Environments ◽  
Receiver Dcb ◽  
German Aerospace ◽  
Global Navigation Satellite ◽  
Academy Of Sciences

Abstract. The differential code bias (DCB) of global navigation satellite systems (GNSS) is an important error source in ionospheric modeling, which was generally estimated as constants every day. However, the receiver DCB may be changing due to the varying space environments and temperatures. In this paper, the receiver DCB of BeiDou Navigation Satellite System (BDS) is estimated as the changing parameter within one day with epoch-by-epoch. The BDS receiver DCBs are analyzed from 30 days of multi-GNSS experiment observations. The comparison of estimated receiver DCB of BDS with the DCB provided by German Aerospace Center (DLR) and Chinese Academy of Sciences (CAS) shows a good agreement. The root mean square (RMS) values of receiver DCB are 0.43 and 0.80 ns with respect to DLR and CAS, respectively. In terms of the intra-day variability of receiver DCB, most of the receiver DCBs show relative stability within one day with the intra-day standard deviation (STD) of less than 1 ns. However, larger fluctuations with more than 2 ns of intra-day receiver DCB are found. Besides, the intra-day stability of receiver DCB calculated by the third-generation BDS (BDS-3) and the second-generation BDS (BDS-2) observations is compared. The result shows that the intra-day stability of BDS-3 receiver DCB is better than that of BDS-2 receiver DCB.

Sign in / Sign up

Export Citation Format

Share Document