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EGNOS Services

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EGNOSEGNOS
Title EGNOS Services
Edited by GMV
Level Basic
Year of Publication 2011
Logo GMV.png

EGNOS (European Geostationary Navigation Overlay Service) is the European Satellite Based Augmentation Service (SBAS) that provides services based on the Global Positioning System (GPS) signals as well as enhanced accuracy and integrity information.

EGNOS supports three services:[1] the Open Service (OS), the Safety of Life Service (SoL), and the Commercial Data Distribution Service (EDAS).

Introduction

EGNOS missions[2] support a wide range of applications. For this reason and to ease a joint service provision with Galileo, Mission requirements are stated in terms of different Services that EGNOS will support, namely:

The service diversity provided by EGNOS will support a wide range of applications, user communities and domains.

EGNOS Open Service

Accuracy improvement gained with EGNOS Open Service

On the 1st October 2009, the European Commission declared that EGNOS' basic navigation signal was operationally ready as an open and free service. In making this announcement, EGNOS Open Service[3] started to provide European users with unprecedented positioning precision by improving the accuracy of standalone GPS.

The continuous monitoring of the EGNOS signal shows accuracy gains with respect to GPS within one to two meters and is available more than 99 percent of the time.[4]

EGNOS Safety of Life

The second key milestone in the EGNOS Programme was the declaration of the EGNOS SoL Service[5] operational. On the 2nd March 2011, the European Satellite Services Provider (ESSP)[6] declared[7] the Safety-of-Life (SoL) signal officially available for aviation with the authorization of the European Commission (EC) to provide the service. At this point message type 0 (MT0) that used to transmit the same contents as a regular MT2 message before certification of EGNOS for civil aviation was removed. This service supports, since its announcement, a great number of applications in the transport domain and renders safety-critical operations safer. Moreover, it provides a valuable integrity message to inform the user within six seconds in case of a malfunction of the signal.

The European Union has expressed its commitment to the long term support of EGNOS,[8] which will provide services along with Galileo when it becomes operational.

In the same way, the European Commission is planning to extend the coverage of the GEO satellites transmitting the EGNOS signal. While the signal currently covers most European states, it has the built-in capability to extend the coverage area to other regions, such as countries on the EU’s borders and North Africa[9]. On March 3, 2015 the SAFIR (Satellite navigation services for AFrIcan Region) project has officially launched the EGNOS-Africa Joint Programme Office in a ceremony in Dakar, Senegal. SAFIR started on January 15, 2013 and is part of the Africa-EU long-term strategic partnership that aims to enhance safety in air transport. The project covers the set-up, staffing and operations of an EGNOS-Africa Joint Programme Office, and sets up and supports a number of technical working sessions composed of regional stakeholders concerned with GNSS/EGNOS in sub-Saharan Africa.[10].

EGNOS Commercial Data Distribution Service

Potential application where professional GNSS services could be provided through diverse communication channels by integrating EDAS

Additionally, the provision of EGNOS commercial products as a result of the Commercial Data Distribution Service will provide added value to Navigation applications, commercial products and will widen the extent of EGNOS applicability to a vast number of environments and purposes.

EDAS will permit users to access additional data that is not provided by the EGNOS Signal broadcast by the geostationary satellites. Some examples of potential applications that could be provided are mentioned in EGNOS Open Service Definition Document:[3] provision of EGNOS information in the RTCM format; EGNOS pseudolites; provision of EGNOS services through RDS, DAB, Internet; accurate ionospheric delay/TEC maps; provision of RIMS data; provision of performance data (e.g. XPL availability maps, GIVE maps, etc.); provision of EGNOS message files.

EDAS is the technical core of the EGNOS Commercial Data Distribution Service and provides the opportunity to deliver EGNOS data to users who cannot always view the EGNOS satellites (such as in urban canyons) or to support a variety of other value added services, applications and research programs. In 2006, the European Commission through the GJU (now superseded by the European GNSS Agency, the GSA) commissioned the EDAS system. EDAS allows any authorized entity to plug into EGNOS to receive the internal data collected, generated and delivered by EGNOS for free. Although the idea of providing GNSS data streams in real time is far from being new, EDAS has some key differentiators, the most important one is probably the service reliability. Other benefits that EDAS brings are the high data rate (1Hz), the dissemination of the EGNOS message broadcast by each GEO satellite and the provision of GLONASS raw measurements. Additionally EDAS provides the raw data of the 34 Ranging and Integrity Monitoring Stations (RIMS) and Navigation Land Earth Stations (NLES). EDAS offers ground-based access to EGNOS data, it is the single point of access for the data collected and generated by the EGNOS infrastructure and it represents the terrestrial commercial data service provided by EGNOS. More detailed information about EDAS could be found in the following link: https://gssc.esa.int/navipedia/index.php/EGNOS_Data_Access_Service_(EDAS)


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