EGNOS Data Access Service
Background & Objectives
The EDAS-N project examines how the current EGNOS Data Access Service (EDAS) should evolve to meet user needs between 2020 and 2030. On the basis of its analysis, it proposes 8 new EDAS services.
EGNOS (European Geostationary Navigation Overlay Service) provides augmentation to the Global Positioning System (GPS) Standard Positioning Service (SPS) since 2011. EGNOS augments GPS by using the L1 (1,575.42 MHz) Coarse/ Acquisition (C/A) civilian signal function, which broadcasts correction data and integrity information for positioning and navigation applications over Europe.
EGNOS provides three services:
- Safety of Life (SoL) Service, which is intended for transport applications in areas where lives could be endangered if the performance of the navigation system is degraded below specific accuracy limits without alerting the user within a specified time.
- Open Service (OS), which provides timing and positioning services to any user equipped with an appropriate GPS/SBAS compatible receiver.
- EGNOS Data Access Service (EDAS), which is intended for users who require EGNOS products for commercial and professional use.
EDAS provides data from EGNOS' ground infrastructure to promote the development of applications for professional and commercial use. The next generation of EGNOS – EGNOS V3 – will augment the GPS and Galileo satellite constellations in the L1 and L5 bands. It will also extend the service area to cover the entire EU.
The EDAS-N project defines the potential evolution of EDAS between 2020 and 2030. As EDAS is expected to disseminate EGNOS V3 data over this period, the analysis focuses on what additional features could help generate new EDAS services for users and service providers.
The EDAS-N project defined how the current EGNOS EDAS should evolve to meet more demanding user needs between 2020 and 2030. The analysis looked at potential new EDAS services and their market uptake. It also estimated their capital expenditure and operating expense. The project proposed a final set of 8 new EDAS-based services, and defined their implementation schedule.
The uptake of the next generation of EDAS is estimated at 178 direct users (mainly service providers) and 350,000 indirect users by 2030.
Work performed & results
The EDAS-N project carried out three interrelated tasks:
- User Domain Analysis: Interviews were conducted with 34 expert stakeholders covering 24 global navigation satellite systems (GNSS) applications across 9 market segments. The aim was to define key services and products that could benefit EDAS-N users and service providers.
- EDAS New Service Definition: 11 EDAS candidate services were originally identified and characterised. Following consultation with GNSS experts, 8 of these 11 were selected for the final EDAS-N portfolio.
- Cost-Penetration Analysis: An assessment was done on the cost of implementation and expected market penetration of the 8 EDAS candidate services. This analysis will support a decision about the potential implementation of new EDAS services and products.
The following EDAS-N service portfolio was proposed:
- Space Weather Alerts: EDAS could provide space weather alerts by sending information from external space weather international institutions and by monitoring the real-time ionosphere state through EGNOS augmentation messages.
- EGNOS-based VRS DGNSS Corrections: EDAS could broadcast differential GNSS (DGNSS) corrections derived from EGNOS augmentation messages (known as Virtual Reference Station – VRS) from any location in the EGNOS service area.
- Satellite Alerts: EDAS could offer GPS and Galileo satellite alerts to warn users about events observed in the satellites monitored by EGNOS.
- Authenticated EGNOS Messages: EDAS could disseminate a sequence of satellite-based augmentation systems (SBAS) messages introducing the authentication credits on the SBAS message themselves or through the emulation of another signal that would be used for authentication purposes. This potential EDAS service could also serve as an initial proof of concept for a feature that might be implemented in the EGNOS Signal In Space.
- Galileo Sensor Stations (GSS) raw data: the dissemination via EDAS of GNSS raw data from GSS in addition to EGNOS Ranging Integrity Monitoring Stations (RIMS) could increase Real-Time Kinematic (RTK) and DGNSS coverage and could be used in ionospheric and tropospheric models for high accuracy services.
- Station Status service: EDAS could provide a status flag for each station broadcasting raw data. These status flags could be useful for certain applications. For example, RTK users could use them to detect and discard low quality data.
- EGNOS messages through NTRIP: an upgrade of the current EDAS data transmitted through the Networked Transport of RTCM via Internet Protocol (NTRIP) service could broadcast EGNOS dual-frequency Galileo/GPS augmentation messages.
- Precise Point Positioning (PPP) service: EDAS could provide PPP messages based on GPS L1/L5 and Galileo E1/E5a signals through NTRIP. This would support applications that need highly accurate positioning.
In addition to these services, EDAS would continue to provide current EDAS legacy services, as well as EGNOS data from the augmentation of Galileo.