User-Oriented ICT Cloud Architecture for High-Accuracy GNSS-Based Services

We introduce a new information and communication technology (ICT) cloud-based architecture for Global Navigation Satellite System (GNSS) high-accuracy solutions, offering also a commercial overview of GNSS downstream market to show how the developed innovation is thought to fit in the real context. The designed architecture is featured by dynamic scalability, increased integrity, and greater agility of the ICT system. The novelty of the solution developed is a customized ICT architecture, obtained through unique and privileged access to user communities in the frame of the H2020 project TREASURE, allowing the development of a solution entirely driven by user needs. The economic outlook of GNSS downstream markets evolution highlights how the technology proposed effectively matches the evolving business environment, specifically in regard to the increasing need for flexibility and competitive advantage deriving from services. The simultaneous adoption of the technical and commercial perspective is meant to offer interesting findings to both the scientific community and GNSS industry, creating synergies previously unexplored.

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Improving DGNSS Performance through the Use of Network RTK Corrections

Remote Sensing ◽

10.3390/rs13091621 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1621

Author(s):

Duojie Weng ◽

Shengyue Ji ◽

Yangwei Lu ◽

Wu Chen ◽

Zhihua Li

Keyword(s):

Carrier Phase ◽

Local Area ◽

Satellite System ◽

High Accuracy ◽

Single Frequency ◽

Baseline Length ◽

Low Latitude ◽

Phase Measurements ◽

Network Rtk ◽

Global Navigation Satellite

The differential global navigation satellite system (DGNSS) is an enhancement system that is widely used to improve the accuracy of single-frequency receivers. However, distance-dependent errors are not considered in conventional DGNSS, and DGNSS accuracy decreases when baseline length increases. In network real-time kinematic (RTK) positioning, distance-dependent errors are accurately modelled to enable ambiguity resolution on the user side, and standard Radio Technical Commission for Maritime Services (RTCM) formats have also been developed to describe the spatial characteristics of distance-dependent errors. However, the network RTK service was mainly developed for carrier-phase measurements on professional user receivers. The purpose of this study was to modify the local-area DGNSS through the use of network RTK corrections. Distance-dependent errors can be reduced, and accuracy for a longer baseline length can be improved. The results in the low-latitude areas showed that the accuracy of the modified DGNSS could be improved by more than 50% for a 17.9 km baseline during solar active years. The method in this paper extends the use of available network RTK corrections with high accuracy to normal local-area DGNSS applications.

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Updating of digital topographic maps in the new national spatial coordinate system: case Fergana valley in Uzbekistan

Proceedings of the ICA ◽

10.5194/ica-proc-4-31-2021 ◽

2021 ◽

Vol 4 ◽

pp. 1-5

Author(s):

Dilbarkhon Fazilova ◽

Hasan Magdiev

Keyword(s):

Coordinate System ◽

Spatial Data ◽

Information Technologies ◽

Satellite System ◽

Topographic Maps ◽

The North ◽

New Information ◽

Global Navigation Satellite ◽

Geodetic Coordinate System ◽

Geocentric Coordinate System

Abstract. The classical geodetic coordinate system (CS42) in Uzbekistan uses the Krasovsky ellipsoid. The implementation of new information technologies, such as the Global Navigation Satellite System, became the basis for the development of a new national open geocentric coordinate system. This paper describes the development of a distortion grid for transforming horizontal spatial data from the local geodetic datum CS42 to a geocentric datum WGS84 for 1:100000 scale maps of the Fergana Valley in Uzbekistan. A first version of the distortion grid file has been created for transforming between CS42 and WGS84 for the whole territory of the country. The significant influence of the longitudinal drift of the region has been confirmed. The grid was used to transform topographic maps at a scale of 1:100000 for the Fergana Valley. Changing the map datum has shifted the grid of coordinate systems by 70 m in the East and 7 m in the North.

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Variability and Performance of Short to Long-Range Single Baseline RTK GNSS Positioning in Indonesia

E3S Web of Conferences ◽

10.1051/e3sconf/20199401012 ◽

2019 ◽

Vol 94 ◽

pp. 01012 ◽

Cited By ~ 1

Author(s):

Irwan Gumilar ◽

Brian Bramanto ◽

Fuad F. Rahman ◽

I Made D. A. Hermawan

Keyword(s):

Long Range ◽

High Frequency ◽

Carrier Phase ◽

Satellite System ◽

High Accuracy ◽

Gnss Positioning ◽

And Performance ◽

Gnss Network ◽

Single Baseline ◽

Global Navigation Satellite

As the modernized Global Navigation Satellite System (GNSS) method, Real Time Kinematic (RTK) ensures high accuracy of position (within several centimeters). This method uses Ultra High Frequency (UHF) radio to transmit the correction data, however, due to gain and power issues, Networked Transport of RTCM via Internet Protocol (RTCM) is used to transmit the correction data for a longer baseline. This Research aims to investigate the performance of short to long-range single baseline RTK GNSS (Up to 80 KM) by applying modified LAMBDA method to resolve the ambiguity in carrier phase. The RTK solution then compared with the differential GNSS network solution. The results indicate that the differences are within RTK accuracy up to 80 km are several centimeter for horizontal solution and three times higher for vertical solution.

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Ionospheric corrections tailored to the Galileo High Accuracy Service

Journal of Geodesy ◽

10.1007/s00190-021-01581-x ◽

2021 ◽

Vol 95 (12) ◽

Author(s):

A. Rovira-Garcia ◽

C. C. Timoté ◽

J. M. Juan ◽

J. Sanz ◽

G. González-Casado ◽

...

Keyword(s):

Satellite Orbit ◽

Satellite System ◽

High Accuracy ◽

Integer Ambiguity ◽

Electron Content ◽

Confidence Bounds ◽

Total Electron ◽

Phase Measurements ◽

Model Geometry ◽

Global Navigation Satellite

AbstractThe Galileo High Accuracy Service (HAS) is a new capability of the European Global Navigation Satellite System that is currently under development. The Galileo HAS will start providing satellite orbit and clock corrections (i.e. non-dispersive effects) and soon it will also correct dispersive effects such as inter-frequency biases and, in its full capability, ionospheric delay. We analyse here an ionospheric correction system based on the fast precise point positioning (Fast-PPP) and its potential application to the Galileo HAS. The aim of this contribution is to present some recent upgrades to the Fast-PPP model, with the emphasis on the model geometry and the data used. The results show the benefits of integer ambiguity resolution to obtain unambiguous carrier phase measurements as input to compute the Fast-PPP model. Seven permanent stations are used to assess the errors of the Fast-PPP ionospheric corrections, with baseline distances ranging from 100 to 1000 km from the reference receivers used to compute the Fast-PPP corrections. The 99% of the GPS and Galileo errors in well-sounded areas and in mid-latitude stations are below one total electron content unit. In addition, large errors are bounded by the error prediction of the Fast-PPP model, in the form of the variance of the estimation of the ionospheric corrections. Therefore, we conclude that Fast-PPP is able to provide ionospheric corrections with the required ionospheric accuracy, and realistic confidence bounds, for the Galileo HAS.

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High-Accuracy Optical Frequency Atomic Clock

Physics and High Technology ◽

10.3938/phit.30.005 ◽

2021 ◽

Vol 30 (3) ◽

pp. 2-7

Author(s):

Myoung-Sun HEO ◽

Dai-Hyuk YU ◽

Won-Kyu LEE

Keyword(s):

Atomic Clock ◽

Satellite System ◽

High Accuracy ◽

Optical Frequency ◽

Atomic Clocks ◽

Navigation Satellite ◽

Fundamental Constants ◽

Quantum Metrology ◽

Order Of Magnitude ◽

Global Navigation Satellite

Frequencies have been the most accurately measured physical quantity since the second was defined in 1967 based on the microwave atomic transition of a Cs atom. Recently, atomic clocks using optical frequency transitions have shown an order of magnitude better accuracy than microwave clocks. Thanks to their high accuracy and resolution, atomic clocks have become a new tool for investigations involving fundamental science and technology, such as the search for dark matter, gravitational wave detection, the temporal variation of fundamental constants, relativistic geodesy, quantum metrology, and the advanced Global Navigation Satellite System (GNSS). In addition, a redefinition of the second based on the optical frequency is expected. In this paper, we review the principles and applications of optical clocks.

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Taiwan’s Economy in 2017: Boosted by Apple’s Great Appetite

East Asian Policy ◽

10.1142/s1793930518000089 ◽

2018 ◽

Vol 10 (01) ◽

pp. 92-104

Author(s):

Min-Hua CHIANG

Keyword(s):

Global Economy ◽

Multinational Firms ◽

Government Expenditure ◽

Economic Growth Rate ◽

New Information ◽

Global Demand ◽

Information And Communication ◽

Production Relations ◽

Near Term ◽

Economic Outlook

The strong global demand for new information and communication technology devices had pushed Taiwan’s economic growth rate in 2017 to 2.84%, from 1.41% in 2016. The improving global economy, growth in minimum wage and rising government expenditure are encouraging factors in the near term. Taiwan’s future economic outlook hinges on its technological capability vis-à-vis other regional peers, close production relations with global multinational firms and adaptation to other new consumption products.

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SBAS/EGNOS for Maritime

Journal of Marine Science and Engineering ◽

10.3390/jmse8100764 ◽

2020 ◽

Vol 8 (10) ◽

pp. 764

Author(s):

Manuel Lopez-Martinez ◽

José-Manuel Álvarez ◽

José-Maria Lorenzo ◽

Carlos Garcia Daroca

Keyword(s):

Global Positioning System ◽

Service Provision ◽

Satellite System ◽

User Communities ◽

Global Positioning ◽

Primary Means ◽

Augmentation Techniques ◽

Maritime Navigation ◽

Gnss Receivers ◽

Global Navigation Satellite

The Global Navigation Satellite System (GNSS) has become the primary means of obtaining Position, Navigation, and Timing (PNT) information at sea. The current capabilities of the Global Positioning System (GPS) constellation, although adequate for ocean navigation, have some shortfalls for coastal navigation: some user communities have a need for enhanced performance and they can benefit from the available “augmentation” techniques, resulting in improved GPS performance. Nowadays, the users can take advantage of Satellite-Based Augmentation Systems (SBASs). The maritime domain has been used SBAS for several years and it is supported by GNSS receivers used in the recreational and professional sectors. The SBAS/European Geostationary Navigation Overlay Service (EGNOS) can be used to complement the differential GNSS (DGNSS) for the provision of enhanced accuracy and integrity information with additional benefits. There are different possible solutions for the transmission of SBAS/EGNOS information to maritime users, considering that the corrections can be available from different transmission means. The different options for the use of SBAS for maritime navigation, the benefits brought to mariners, as well as the associated regulations, standardization and service provision aspects, are presented in this article.

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On the performance of GNSS levelling over steep slopes

Boletim de Ciências Geodésicas ◽

10.1590/s1982-21702012000400008 ◽

2012 ◽

Vol 18 (4) ◽

pp. 645-660 ◽

Cited By ~ 3

Author(s):

R. Cuneyt Erenoglu ◽

Mehmet Ali Yucel ◽

Atinc Pirti ◽

D. Ugur Sanli

Keyword(s):

Satellite System ◽

High Accuracy ◽

Short Baseline ◽

Solution Strategies ◽

Baseline Solution ◽

3D Positioning ◽

3D Information ◽

Global Navigation Satellite ◽

Steep Slopes ◽

New Strategies

In geodetic applications variety, one of the main current focuses is recently to determine the heights of ground stations with high accuracy. Specially the possibility of acquiring 3D information of the point positioning with high accuracy is opening up new strategies of investigating the heighting. Global Navigation Satellite System (GNSS) for 3D positioning is undergoing rapid developments and GNSS heighting can be an alternative to terrestrial techniques of height measurements. This paper presents a research study on the use of GNSS heighting in the case of steep slopes and multipath issue. Short baseline solution strategies were performed by using Bernese Software v. 5.0. The analysis results are also compared to the results of techniques of the terrestrial levelling. The results show that GNSS can be used as an practical surveying method to the terrestrial levelling with comparable accuracies. Furthermore, one can save up to 1 hour using GNSS instead of geometric levelling over a steep slope of a 100 m. On the other hand, as usual multipath is the primary error source decreasing the efficiency of GNSS, and it has been studied experimentally in this paper.

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Background and Recent Advances in the Locata Terrestrial Positioning and Timing Technology

Sensors ◽

10.3390/s19081821 ◽

2019 ◽

Vol 19 (8) ◽

pp. 1821 ◽

Cited By ~ 1

Author(s):

Chris Rizos ◽

Ling Yang

Keyword(s):

Literature Review ◽

Global Navigation Satellite System ◽

Satellite System ◽

High Accuracy ◽

Urban Environments ◽

Navigation Satellite ◽

Positioning Systems ◽

Comprehensive Literature Review ◽

The World ◽

Global Navigation Satellite

Global Navigation Satellite System (GNSS) is the most widely used Positioning, Navigation, and Timing (PNT) technology in the world today, but it suffers some major constraints. Locata is a terrestrial PNT technology that can be considered as a type of localised “constellation”, which is able to provide high-accuracy PNT coverage where GNSS cannot be used. This paper presents a comprehensive literature review of the Locata technology and its applications. It seeks to answer questions, such as: (1) What is Locata and how does it work? (2) What makes Locata unique compared with other terrestrial positioning systems? (3) How has Locata been used in different applications for accurate PNT? (4) What are the current challenging issues that may restrict its further adoption for custom-grade navigation in urban environments?

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The ionosphere prediction service prototype for GNSS users

Journal of Space Weather and Space Climate ◽

10.1051/swsc/2019038 ◽

2019 ◽

Vol 9 ◽

pp. A41 ◽

Cited By ~ 1

Author(s):

Sreeja Vadakke Veettil ◽

Claudio Cesaroni ◽

Marcio Aquino ◽

Giorgiana De Franceschi ◽

Francesco Berrili ◽

...

Keyword(s):

Satellite System ◽

Modern Life ◽

Web Based ◽

Service Chain ◽

Ionospheric Effects ◽

User Communities ◽

Receiver Performance ◽

Set Up ◽

Global Navigation Satellite ◽

The Impact

The effect of the Earth’s ionosphere represents the single largest contribution to the Global Navigation Satellite System (GNSS) error budget and abnormal ionospheric conditions can impose serious degradation on GNSS system functionality, including integrity, accuracy and availability. With the growing reliance on GNSS for many modern life applications, actionable ionospheric forecasts can contribute to the understanding and mitigation of the impact of the ionosphere on our technology based society. In this context, the Ionosphere Prediction Service (IPS) project was set up to design and develop a prototype platform to translate the forecast of the ionospheric effects into a service customized for specific GNSS user communities. To achieve this overarching aim, four different product groups dealing with solar activity, ionospheric activity, GNSS receiver performance and service performance have been developed and integrated into a service chain, which is made available through a web based platform. This paper provides an overview of the IPS project describing its overall architecture, products and web based platform.

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