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EGNOS Performances

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Title EGNOS Performances
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 complements the existing satellite navigation services provided by the US Global Positioning System (GPS) using the L1 C/A signal. EGNOS will augment both GPS and Galileo in the future (in EGNOS V3) using L1 and L5 frequencies.

EGNOS performances are usually described in terms of accuracy, integrity, availability and continuity.

EGNOS Performances Requirements

EGNOS has been designed to meet SBAS performance requirements for civil aviation operations down to Localizer Performance with Vertical Guidance (LPV) minima but EGNOS service might also be used in a wide range of other application domains (e.g. maritime, rail, road...):[1][2]

Service Service Coverage Accuracy (95%) Integrity Continuity Availability
Lateral Vertical Integrity TTA
Open Service EU25 States (plus Norway and Switzerland) land masses 3m 4m - - - 0.99
En-route and NPA FIRs of ECAC 96 220m - 1 – 1x10⁻⁷/h Less than 6 seconds <1 – 1x10⁻³ per hour in most of ECAC <1 – 2.5x10⁻³ per hour in other areas of ECAC 0.999 in all ECAC
APV-I & LPV200 Land Masses of ECAC 96 3m 4m 1 – 2x10⁻⁷/approach Less than 6 seconds <1 – 1x10⁻⁴ per 15 seconds in the core of ECAC 1 –5x10⁻⁴ per 15 seconds in most of ECAC landmasses 0.99 in most of ECAC landmasses

Typical Performances

The typical performances provided by EGNOS are presented in the next figures. For the computation, the day 6th December 2018, considered to be a representative day, has been selected. The images have been obtained using gmvBrave tool.[3]

Monitoring of EGNOS Performances

EGNOS performances are being monitored continuously by several entities, such as ESSP[4] and ESA.[5]

The EGNOS performance monitoring done by ESSP[4] includes figures on achieved availability, continuity and integrity. In addition, it forecasts the performances in terms of availability and integrity.

The monitoring done by ESA[5] is twofold. On the one hand, the messages, as broadcast by the EGNOS satellites, are analyzed to determine the status of several parameters, such as the GPS satellites which are augmented by EGNOS, the level of monitoring of the ionosphere over Europe or the achieved protection levels. On the other hand, ESA monitoring environment allows to select different reference stations and depicts the accuracy and integrity obtained for those sites.