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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 currently augments the GPS L1 (1575.42 MHz) Coarse/Acquisition (C/A) civilian signal. EGNOS will augment both GPS and Galileo in the future, using L1 and L5 (1176.45 MHz) frequencies.

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

Introduction

EGNOS supports a wide range of applications through the following Services:

The service diversity provided by EGNOS supports a wide range of applications, user communities and domains[2].

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[5] 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 Safety-of-Life service is tailored to safety-critical transport applications in various domains, in particular the service is compliant with the aviation requirementsfor APV-1 and Category I precision approaches. The operational use of the EGNOS SoL service in other domains may require specific authorisation by the relevant authorities in the applications sectors concerned.

The European Union has expressed its commitment to the long term support of EGNOS,[7] 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[8]. On March 3, 2015 the SAFIR (Satellite navigation services for AFrIcan Region) project 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.[9].

EGNOS Data Access Service (EDAS)

EDAS architecture and services that could be provided through diverse communication channels (Source: EDAS in EGNOS ESSP website [10].)

Additionally, the provision of EGNOS commercial products as a result of the EGNOS Data Access Service (EDAS) provides added value to Navigation applications, commercial products and widen the extent of EGNOS applicability to a vast number of environments and purposes.

EDAS is the EGNOS terrestrial data service and offers ground-based access to EGNOS data in real time and also in a historical FTP archive to the authorised users.

EDAS 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. EDAS also permits users to access additional data that is not provided by the EGNOS Signal broadcast by the geostationary satellites. The EGNOS EDAS is available since 26 July 2012 [11].. 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 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 EDAS Service Definition document[11].

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