GNSS: Agenda and approach
The United Nations Programme on Space Applications, the Office for Outer Space Affairs held the United Nations International Meeting on Applications of Global Navigation Satellite Systems at the United Nations Office at Vienna, Vienna International Centre, in Vienna from 12 to 16 December 2011. The Meeting was co-sponsored by the United States of America through International Committee on GNSS (ICG).
The five-day International Meeting on the applications of GNSS was aimed to contribute to international cooperation by providing opportunity to exchange updated information on the use of GNSS technology and its applications. The specific objectives of this International Meeting were: (i) to examine the trends that are apparent in the worldwide development of GNSS and how they will affect the growing population of civil users of satellite-positioning technologies; (ii) to review on-going and planned initiatives as well as case studies that could contribute to the wider use of GNSS technology and its applications, including the possibility of one or more national, regional and international pilot projects, in which interested institutions could incorporate the use of GNSS technology; (iii) identify a functional partnership that could be established in order to promote innovative GNSS-enabled applications, as well as recommend how such a partnership could be established through voluntary actions that could include Governments, international organizations, research and development institutions, academia and other relevant stakeholders; (iv) define recommendations and findings to be forwarded for consideration by ICG and its working groups.
At the opening of the Meeting, introductory and welcoming statements were made by the Director of the Office for Outer Space Affairs and the representative of the United States, as the co-chair of the Action Team on GNSS. The keynote presentation, entitled “ICG and its programme on GNSS applications” was made by a representative of the Office for Outer Space Affairs, in which the work carried out by the Office in supporting activities to promote the use of GNSS-based applications was described.
A total of 41 presentations were made by invited speakers from both developing and developed nations. A total of 75 specialists in satellite navigation systems were invited to attend the International Meeting. The following 36 Member States were represented at the International Meeting: Algeria, Austria, BruneiDarussalam, Burundi, China, Colombia, Costa Rica, Croatia, Ecuador, Egypt, France, Germany, India, Indonesia, Israel, Italy, Japan, Latvia, Madagascar, Morocco, Nigeria, Pakistan, Republic of Moldova, Romania, Russian Federation, Serbia, Spain, Swaziland, Thailand, the Philippines, Tunisia, Turkey, United Arab Emirates, United States of America, and Uzbekistan. The Office for Outer Space Affairs, the European Space Agency (ESA), International Association of Institutes of Navigation (IAIN), International GNSS Service (IGS), International Telecommunication Union (ITU) and Space Generation Advisory Council (SGAC) were also represented.
The presentations made at the Meeting and the abstracts of the papers, as well as the Meeting programme and background materials, are available from the website of the Office for Outer Space Affairs (www.unoosa.org).
Participants were divided into four working groups on the basis of their areas of expertise and interest: future of the ICG; GNSS applications and space weather effects on GNSS; regional reference frames and systems; and GNSS education curriculum and ICG information centres.
Working group on future of the ICG
At the Seventh Meeting of the Providers’ Forum held in conjunction with the Sixth Meeting of the ICG, it was agreed that the future role and work of the ICG and its Providers’ Forum should be reviewed. The decision to begin discussions on the future development of ICG, as a new agenda item at the Providers’ Forum meeting, emphasized that ICG shall play an important role in future GNSS developments and their implications for civil use and performance. ICG Member States focused on the issues related to ICG’s effective functioning and current format as a body established to promote cooperation on matters of mutual interest related to civil satellite-based positioning, navigation, timing, and value-added services, as well as the compatibility and interoperability of GNSS22. The meeting of the working group on the future of the ICG was chaired by the United States of America, as the co-chair of the Action Team on GNSS. In considering the structure, role and objectives of the ICG and its Providers’ Forum in general, the working group prepared an informal note on a number of possible options and modalities that could strengthen the effectiveness of the ICG in the future.
Working group on GNSS applications and space weather effects on GNSS
The working group identified GNSS as the global public goods for worldwide enhancement of the quality of life, particularly with GNSS utilizations such as (i) applications for individual handsets and mobile phones, (ii) road transport, (iii) aviation, (iv) maritime transport, (v) precision agriculture and environment protection, and (vi) civil protection and surveillance.
Placing emphasis on applications development, the working group strongly recommended protection of GNSS spectrum and noted that use of GNSS for sustainable development in application areas, such as navigation, surveying, and mapping, can yield significant societal benefits.
In the context of future developments of GNSS and its applications, the working group identified the achievement of interoperability between different GNSS, and provision of sustained and balanced quality of positioning, navigation, and timing GNSS services as the key elements in order to achieve maximum civil user benefit. It was noted that the combination of GNSS constellation, and augmentation satellites will provide far superior satellite geometry and signal availability than with one GNSS alone, and it will make a big difference to both present and future applications. In this regard, multi-GNSS demonstration campaigns were encouraged.
The working group noted that space weather refers to the environmental conditions in the Earth’s magnetosphere, ionosphere and thermosphere due to the Sun and the solar wind that can infl uence the functioning and reliability of spaceborne and ground-based systems and services or endanger property or human health.
The working group also noted that space weather accounts for the most substantial errors experienced by GNSS systems and their users. Predictions of space weather are important to the GNSS community. Scientific efforts applied to monitoring and predicting space weather and resources available and under development to aid GNSS users in dealing with all possible adverse effects of space weather need to be increased. In this regard the International Space Weather Initiative (ISWi) was emphasized.
The working group specifically addressed and highlighted the multi-GNSS demonstration campaign undertaken in the region of Asia and the Pacific, taking into account the fact that this region is an unique area where multi-GNSS constellations and new modernized signals will be able to be utilized sooner than in other regions in the world due to the contributions from regional constellations such as the second stage of Beidou/COMPASS of China, IRNSS of India, and QZSS of Japan, in addition to global GNSS constellations as GPS, GLONASS, and Galileo.
The working group recognized a number of important multi-GNSS benefits: (i) multi-GNSS use can provide not only the increment of the number of navigation satellites but also additional signals and frequencies, (ii) multi-GNSS use is a method to reduce the vulnerability and increase the reliability and robustness of GNSS services. Additionally, the incremental increase of the number of visible satellites using the same frequency can support Receiver Autonomous Integrity Monitoring (RAIM) technologies.
Working group on regional reference frames and systems
The working group recognized that reference networks, comprised of permanent stations, operating GNSS receivers on a continuous basis, provide the fundamental infrastructure required to meet the needs of geodesy, geosciences, navigation, surveying, mapping, and other applications. The working group encouraged national and regional authorities to support initiatives of regional reference frames and systems such as an International Association of Geodesy Reference Frame Sub-Commission for Europe (EUREF), the European Position Determination System (EUPOS), the Geocentric Reference System for the Americas (SIRGAS), African Geodetic Reference Frame (AFREF), and Asia-Pacific Reference Frame (APREF). A consolidated list of reference frames and systems, that are used by national authorities, agencies, or regional organizations, and their prospective plans for future development should be made available on the ICG Information Portal.
The working group encouraged the use of multi-constellation GNSS signals in reference networks.
The regional reference frames should use, if possible, the same frame (best or latest version) realization for ensuring the trans border data exchange compatibility and interoperability. The best solution is to achieve consensus with neighbouring countries on one reference frame realization.
The utilization of GNSS Real-Time Kinematic (RTK) technique had encouraged users to apply GNSS reference receivers to support the growing number of applications of high accuracy positioning for engineering, precision agriculture, etc. In this regard the working group called for the set up of more permanent stations, or consider the existing dense GNSS Continuously Operating Reference Station (CORS) network infrastructure in order to improve the velocity field of reference frame and provide more adequate information for static and kinematic applications.
Depending on the expected accuracy and type of the required measuring method (static or RTK), the definition of the frame as a static reference frame or as a frame realization with applied velocities should be defined. For the determination of velocity of reference frame repeated static measurements are required. The best method to monitor this is to install GNSS CORS.
The working group felt that the establishment of GNSS positioning services, e.g. RTK networks, is an urgent need for many countries in the world. The working group recommended the provision of a document to the public that describes the procedure to set up a national GNSS positioning service. Geodynamic activities in specific regions need to be considered and may cause different recommendations for stable regions and regions prawn to large tectonic movements.
GNSS education curriculum and ICG information centres
The working group noted the available capacity building opportunities and the status of operation of the UN-affiliated Regional Centres for Space Science and Technology Education, located in Brazil and Mexico for Latin America and the Caribbean, in India for Asia and the Pacific, and in Morocco and Nigeria for Africa. The working group had before it the updated education curricula for (i) remote sensing and GIS, (ii) satellite meteorology and global climate, (iii) satellite communications, and (iv) space and atmospheric science.r>
The working group continued the development of the GNSS Education Curriculum by taking into account GNSS course outlines as used at the university level in a number of developing and industrialized countries. The incorporation of elements of GNSS science and technology into university-level education curricula served a dual purpose. It could enable countries to take advantage of the benefits inherent in the new technologies, which, in many cases, are spin-offs from space science and technology. Utilize the educational system, introduce the concepts of high technology in a nonesoteric fashion and help create national capacities in science and technology in general. Currently there are strong attempts world wide to introduce GNSS in terms of science, technology, and applications as a stand alone discipline in the university level teaching curricula.
The working group took note of the fact that the GNSS Education Curriculum under development differs from most of those available in literature and on the World Wide Web. In this regard the GNSS Education Curriculum is a unique result that emanated from the deliberations of the series of regional workshops on GNSS applications since 2006. The working group also agreed to develop as part of the GNSS Education Curriculum a module for hands-on GNSS exercises based on data and equipment used for space weather monitoring.
Based on the working groups recommendations, the International Meeting concluded that an increasingly important role of GNSS science, technology, and education calls for the establishment of an International Centre for GNSS Science, Technology, and Education. This conclusion was emphasised by the ten years of achievement of the United Nations on GNSS.
The International Meeting recommended that the United Nations should lead, with the active support of China and relevant scientific organizations, an international effort to establish an International Centre for GNSS Science, Technology, and Education in an existing national educational and research institution. Beihang University24 of China, offered to host this Centre.
The Centre might grow into a network of centres, focusing on GNSS science, technology, and education, around the world – all dedicated to advancement of GNSS research, applications, and education.
The Centre will cooperate with the United Nations affiliated Regional Centres for Space Science and Technology Education, located in India, Mexico/ Brazil, Morocco, and Nigeria, the International Centre for Space Weather Science and Education, located in Japan, and other centres of excellence in space science, technology, and education.
The Centre will report annually to the ICG Working Group on Information Dissemination and Capacity Building lead by the United Nations Office for Outer Space Affairs. The Centre will also act as the information centre for ICG.