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Analysis of Primary Position Validation in ECDIS System
Published in Adam Weintrit, Tomasz Neumann, Advances in Marine Navigation and Safety of Sea Transportation, 2019
D. Šakan, S. Žuškin, D. Brčić, S. Valčić
Satellite navigation is used in many different systems and areas of application, for positioning and very precise time measurement. The position is determined as an intercept of position spheres of at least three satellites. The radius of the sphere is range calculated as a function of time elapsed from the moment signal is sent from the satellite, and the known speed of signal propagation, until reception at the user’s receiver. Global Navigation Satellite Systems (GNSS) is any satellite constellation that provides continuous Position, Navigation and Timing (PNT) capabilities. Satellite positioning is extremely precise when compared with previously described methods, however accuracy depends on satellite geometry, signal strength and obstructions, atmospheric conditions, end-user receiver design characteristics and quality. Also, as with any electronic position system, it is susceptible to outages, malfunctions, malpractice, degradation and intentional interferences. At present, USA’s Global Position System (GPS) is the most used satellite navigation system. Despite terms GPS and GNSS are sometimes used interchangeably, GPS is not the only GNSS system available. Russian Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS) is also globally available. China’s BeiDou Navigation Satellite System (BDS) started with provision of global PNT services on December 28th, 2018 – one year before the planned start. The European Union’s Galileo system, with 22 Full Operational Capability (FOC) satellites is still in its initial service phase.
A new method for integrated navigation of hypersonic cruising aircraft using non-Keplerian orbits
Published in Yigang He, Xue Qing, Automatic Control, Mechatronics and Industrial Engineering, 2019
H.L. Li, D.W. Wu, B. Zhang, B.F. Yang, Y.H. Zhao
In actual application, however, the INS/GNSS/CNS integrated navigation system uses three dissimilar sensors to obtain observational information. The parameters concerned in the integrated navigation system are the position and velocity information, but only the platform misalignment angle is observed in the CNS, which does not provide the position and velocity information for the filter directly. For the same state, only two sensors (INS/GNSS or INS/CNS) are used. In the information fusion, the information from each sub-filter is different. Therefore, the output information from two sub-filters if the federal Kalman filtering is straightly used is an isomerous in the main filter, which leads to the squared error matrix estimator of the main filter being diverged (Yang et al., 2013). Meanwhile, the satellite navigation equipment is vulnerable to interference or shielding during extended-time and long-distance flights (He et al., 2014). All of these problems make the traditional INS/CNS/GNSS integrated navigation system inefficient for navigation on extended-time and long-distance HCV flights.
Radio Location, Radio Navigation, and GPS Systems
Published in John G. Webster, Halit Eren, Measurement, Instrumentation, and Sensors Handbook, 2017
Satellite navigation systems use electronic receivers to determine the location of an object within a few meters using time signals transmitted from the line-of-sight satellites. The receivers calculate the time as well as position (longitude, latitude, and altitude) of the object.
Performance analysis of multi-GNSS static and RTK techniques in estimating height differences
Published in International Journal of Digital Earth, 2020
Ahmed Elaksher, Tarig Ali, Franck Kamtchang, Christian Wegmann, Adalberto Guerrero
The Global Navigation Satellite Systems (GNSS) is a multi-constellation system available to civilian users and it encompasses various satellite navigation systems such as NAVSTAR (i.e. GPS), GLONASS, Galileo, and BeiDou (Alkan, Karaman, and Sahin 2005). The accessibility, reliability, and availability of the system is significantly superior compared to individual systems (Li et al. 2015). The quality of GNSS positioning has improved over the last few years because of the improvements in processing algorithms, the addition of more satellites, and the manufacturing of advanced receivers (Wang et al. 2012). For static GNSS surveys, constant accuracies of 5–20 mm and scaler accuracy of one part per million (ppm) are published in Ogaja (2016). Yet to reported 20 mm and one ppm for Real-Time Kinamatic (RTK) surveys. Ghilani and Wolf (2015) highlighted the effect of the satellite configuration on the accuracy of GNSS positioning considering the Vertical Dilution of Precision (VDOP).
Accuracy of human motion capture systems for sport applications; state-of-the-art review
Published in European Journal of Sport Science, 2018
Eline van der Kruk, Marco M. Reijne
Of the EMS systems, the GPS-GLONASS dual frequency system shows a promising range-accuracy combination: 0.04 m accuracy in a range of 15,000 m2. GNSS are satellite navigation systems of which GPS, GLONASS and GALILEO are examples. Satellites transmit data containing information on the location of the satellite and the global time. Since all satellites have a different position, the time it takes for the data to reach the receiver is different, which gives the option of determining the distance of the satellites. If the receiver gets the information from four satellites, the position in 3D can be estimated, although height information is determined 2–3 times worse than horizontal displacement (Berber, Ustun, & Yetkin, 2012). Note that in the graph, all GNSS systems are differential GNSS systems, which have an additional GNSS receiver as a static base station within 5 km of the test site. The measurement of the satellite signals of the base station is combined with the measurements of the mobile GNSS to increase accuracy.