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The 13th Satellite Navigation Summit’s systems update sessions were once again an opportunity for GNSS stakeholders to review the world’s systems, with the GSA providing updates on Galileo and EGNOS.

Speaking at a recent system update session during the Munich Satellite Navigation Summit, the Head of Galileo and EGNOS Programme Management at the Directorate-General for Internal Market, Industry, Entrepreneurship and SMEs (DG GROWTH), Paul Flament, noted his excitement about the major progress Galileo will show this year. According to Flament, the ground segment for Galileo is in place and working well, and all satellite launches are now ensured, with an anticipated six satellites joining the constellation of 12 during the course of the year.

Furthermore, 2016 will see the first quadruple satellite launch using the new Ariane 5 launcher. He says all currently contracted satellites will be launched by the end of 2018, creating a constellation of 26. A tender for the provision of an additional eight satellites by the end of 2020 is currently under way.

The two Galileo satellites that had been launched into incorrect orbits have been moved into more useful positions and can now be used for the search and rescue (SAR) functions, and perhaps also the Open Service. Flament said some testing with receiver manufacturers has shown that their signals are compatible with the service.

Flament further noted that a Galileo Service Definition document is under development, with a public version being released when Galileo Initial Services are launched later in the year. “Initial Services will be launched using the 12 satellites currently in orbit, following a thorough characterisation and observation of the system over the next 4 to 6 months,” he said.

A multi-constellation world

Galileo will soon be joining several other national and regional systems, including GPS, GLONASS and BeiDou, creating a truly multi-constellation environment. Providing an update on the status and modernisation of Global Positioning Systems (GPSs), Harold ‘Stormy’ Martin, Director of the National Coordination Office for Space-based Positioning, Navigation and Timing (PNT), noted there are now 31 operational satellites in orbit – the most there has ever been. He also praised the engineering team who successfully extended satellite battery life by up to 2 years, and noted that the system is gradually decreasing range errors and increasing accuracy year-on-year.

Looking to the future, the GPS III, currently in development, recently saw its first satellite complete thermal vacuum testing. Various upgrades to the ground segment are also planned to enhance cyber security and prepare for the next generation of satellites. Martin concluded by reiterating the USA’s commitment to the free access of civil GNSS signals as a critical element of the global information infrastructure and, in support of this objective, that GPS will show continuous improvement with reliable and predictable performance.

For the Russian point of view, the GLONASS update was provided by Tatiana Mirgorodskaya of the Roscosmos Space Agency. According to her, the 2012 Russian federal budget had secured funding for the programme for 9 years. As a result, performance is improving in terms of accuracy and integrity, and in difficult signal conditions. She also highlighted that the GLONASS-based state emergency system for automobile transport (ERA-GLONASS) is now in service and has proved very effective.

The status of the Chinese BeiDou system (BDS) was outlined by Jun Shen from the China Satellite Navigation Office in Beijing. According to his report, stable operation is being maintained, with accuracy better than 10 metres in some areas. Furthermore, new BDS satellites have an updated signal structure and more accurate clocks. The performance of the system is also gradually improving, and compatibility with other GNSSs is also better. He noted that China is currently working on a BDS SBAS augmentation for aviation, along with a ground-based augmentation system for centimetre-level accuracy.

SBAS too

Space-based Augmentation Systems (SBASs) such as EGNOS were the subject of their own session. The status of the European Geostationary Navigation Overlay Service (EGNOS) was presented by GSA EGNOS Operations and Maintenance Manager, Vincent Brison. According to Brison, EGNOS now offers complete European coverage for the safety of life (SoL) service. He also noted that EGNOS has maintained an accurate service for users during the recent GPS timing glitch of 26 January. “More so, new LPV-200 procedures at European airports are now running at one per week and increasing,” he concluded.

From the US side, according to Jason Burns of the Federal Aviation Administration (FAA), the next satellite launch for the USA’s Wide Area Augmentation System (WAAS) had been delayed by the SpaceX Falcon 9 launcher failures. However, the FAA has a schedule for future releases of WAAS up to 2020.

Dr Takeyasu Sakai from Japan’s Electronic Navigation Research Institute in Tokyo talked about the status of the Japanese QZSS SBAS. He anticipates four satellite operations in 2018, and a seven-satellite configuration by 2023. QZSS SBAS will take over from other systems for sub-metre augmentation in 2020.

EGNOS in Africa?

An insight into the possible expansion of EGNOS over Africa was given by Julien Lapie from the Agency for Aerial Navigation Safety in Africa and Madagascar (ASECNA). “ASECNA is looking to facilitate the cooperative management of a single African sky of 16.1 million square miles,” he said. “This is important because 87 % of Africa is 250 kilometres from a main or regional airport.”

A roadmap for achieving this pan-African SBAS envisions early EGNOS-based services by 2019 or 2020, with provision of full services from 2023 onwards. Although there is a need for more information on ionospheric studies to characterise and optimise the EGNOS model over Africa, results are encouraging. Lapie said he hopes for an ASECNA-EU international agreement in the near future.

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