The Galileo Open Service has been upgraded with three features added to its I/NAV message, one of the four message types broadcast by Galileo satellites. These features are now available to all Galileo Open Service users.
The process of upgrading the Galileo Full Operational Capability constellation satellites has been finalized and the I/NAV improvements are openly accessible through the I/NAV message carried by the E1-B signal. If users have experienced delays when turning on a GNSS device, the recent I/NAV improvements may reduce them significantly, reported the European Union Agency for the Space Programme (EUSPA).
The I/NAV message is now faster and offers more robust positioning. The Reed Solomon Outer Forward Error Correction (RS FEC2) increases demodulation robustness, which enhances the sensitivity. It also improves the overall time to retrieve clock and ephemeris data (time to CED) with the broadcasting of additional, redundant CED information while allowing for the device to restore potentially corrupted data autonomously.
The Reduced CED (RedCED) enables fast initial positioning, with lower than nominal accuracy, by decoding a single I/NAV word, while waiting to receive the four I/NAV words carrying the full-precision CED.
The combination of RS FEC2 and RedCED enables I/NAV to obtain a first course position solution faster and to reduce the time required to obtain a first full accuracy solution (RS FEC2). This translates into a reduced time to first fix (TTFF) for the Open Service users, particularly when operating in harsh environments.
Additionally, the improvements benefit applications working in assisted GNSS (A-GNSS) mode, through the Secondary Synchronisation Pattern (SSP). In A-GNSS mode, when navigation data is received from non-GNSS channels and the receiver’s knowledge of the Galileo System Time is affected by a relatively large error, typically in the order of a few seconds, the clock uncertainty must be resolved quickly and stably.
With the I/NAV improvements, receivers will be able to do this via the new SSP feature, thus reducing the TTFF, also in A-GNSS mode.
While the I/NAV improvements are fully operational, EUSPA will launch a testing campaign open to receiver manufacturers, that will consist of several testing windows. The tests will allow the participants to have a confirmation of the correct implementation of the OS SIS ICD 2.0 — i.e., the right processing of the three I/NAV improvements in their products.
The tests will be conducted at the laboratories of the European Commission’s Joint Research Centre in Ispra, Italy, and of the European Space Agency ESA/ESTEC in Noordwijk, The Netherlands.
EUSPA will assign each applicant to one of the two laboratories depending on the specific conditions and availability.
In 2022, the Galileo GNSS continued to provide the world’s most precise satellite navigation information, to a user base that stands at more than 3.5 billion worldwide. Furthermore, provided services continue to improve and expand, with plans for high-accuracy positioning and signal authentication now reaching fruition.
The European Union Agency for the Space Programme (EUSPA) and the European Space Agency (ESA) continue to enjoy an effective collaboration on the many development, deployment, and evolution activities of the Galileo Programme — each according to their respective responsibilities for service provision and system development with the European Commission (EC) acting as the program manager.
Ranging accuracy performance from January to September 2022.Positioning-related MPLS from January to October 2022.
New Services Launched in 2022
Excellent Performance
Service delivery operations and maintenance of operational systems are managed by EUSPA, which supervises many contracts that carry out the day-to-day activities from dedicated control and monitoring centers throughout Europe. In 2022, Galileo timing, navigation, and SAR/Galileo services were delivered with excellent performances that continue to exceed the formal declarations for minimum performance levels (MPL), which were increased in January, both in terms of absolute accuracy and overall service availability. The entry into service of two additional satellites in May and August, have further consolidated the overall service availability to end users.
Galileo FOC Batch 3 satellite under testing.
Expansion of Service Portfolio
The service provision teams have been able to focus on improvements to, and expansion of, the service portfolio.
The I/NAV improvement will positively impact end users by enabling a faster time to first fix, and updates to the data validity status flags will lead to better protection of users against expired navigation data. These changes are implemented in updates of the onboard software of the satellites being rolled out across the constellation. At present, seven operational satellites have been successfully updated; the complete software upgrade campaign is planned to be completed this summer.
Galileo’s new High Accuracy Service will provide free precise point positioning (PPP) corrections, in the Galileo E6-B data component and by terrestrial means, for Galileo and GPS (single and multi-frequency) to achieve real-time user position improved by up to 10 times. The infrastructure to support an initial service (Phase 1) is nearing completion, and the formal declaration of the service capabilities is planned for early this year.
To provide users with a method of authenticating the received Galileo signals, especially the satellites ephemerides and the Galileo timing parameters, the new Open ServiceNavigation Message Authentication (OSNMA) service enables a receiver to confirm that a navigation message originated from the EU Galileo infrastructure. Many application areas are expected to benefit from this capability, including smart tachographs, telematics and logistics, UAVs, location-based services, and timing services. Having successfully demonstrated the technology behind the service in 2022, including a public observation phase, the roll-out of the Initial Service is planned to take place by the end of the year.
A fourth Medium Earth Orbit Local User Terminal (MEOLUT) in La Réunion will extend the SAR/Galileo Forward Link Service Coverage Area over the Indian Ocean as part of the SAR/Galileo full operational capability (FOC) declaration expected in the first quarter of 2023. The Cospas-Sarsat commissioning of this new station was completed in September 2022, and operational data is already being distributed to Cospas-Sarsat.
Reference documents for the above services can be found at the EUSPA European GNSS Service Centre website, including technical notes, interface control documents and service declaration documents.
SAR/Galileo-related metrics from January to October 2022.Extension of the SAR/Galileo Forward Link Service Coverage Area over the Indian Ocean.
FOC Infrastructure Development Nears Completion
Satellite Production
The production of the third batch of Galileo FOC satellites advanced further in 2022 with the completion of the environmental tests and the system compatibility test campaigns at the European Space Agency Test Centre in Noordwijk, The Netherlands. After 10 years of successful testing, on Oct.18, 2022, the last Galileo FOC satellite (flight model number 34) left the test center to return to the premises of the satellite manufacturer, OHB Systems, in Germany. Testing of the remaining 10 satellites has confirmed that they have been correctly built and will perform well in orbit. The acceptance review of the last couple of satellites will take place this summer.
At the beginning of 2023, the plan is to start in-orbit testing of a quasi-pilot signal on the E5 frequency using the Galileo GSAT201/202 satellites in elliptical orbit. The provision of a signal offering coarse acquisition in Galileo E5-A/GPS L5 can be a distinguishing feature for Galileo with respect to all other constellations to further improve the capability to acquire the E5 signal at low complexity. Following in-orbit testing, the strategy for roll-out of this capability will be assessed with the involvement of receiver manufacturers.
New SAR Galileo MEOLUT facility in Réunion island.
Access to Space
The discontinuation of Soyuz launch services from the Kourou Space Centre in French Guiana, because of the Russia-Ukraine conflict, has caused delays in the two Galileo launches that had been planned for 2022. The Launch 12 campaign had to be interrupted and in March 2022 the FM25 and 26 satellites were put in storage at the Kourou launch base, then returned to Europe in November.
Ariane 6 is the baseline launcher for Galileo satellites to ensure European independent access to space. The remaining Batch 3 satellites will be launched with the Ariane 62 launcher vehicle, the two strap-on solid booster variants of Ariane 6, now undergoing the final stages of development led by prime contractor Ariane Group. Ariane 6’s maiden flight is scheduled to take place in the fourth quarter of 2023.
Ground Segment
An upgrade of the ground control segment, in charge of command and control of the satellite constellation, is being developed by the industrial consortium led by GMV. The upgrades will address resolution of hardware and software obsolescence including cyber security, operability improvements, and a security monitoring overlay.
With the planned increase in the number of satellites in orbit, an additional telemetry tracking and control facility (TTCF) is being deployed in Kourou leading to seven operational TTCF stations in early 2023.
The ground mission segment, in charge of navigation control, is undergoing a complete technological refresh, including hardware/software virtualization performed by an industrial consortium led by Thales France. This upgrade will provide additional robustness, including a system extended contingency mode resilient to outages lasting up to seven days and a new state-of-the-art cyber security monitoring system. It will also provide ranging authentication through encrypted codes on the E6-C signal component for the implementation of the Commercial Authentication Service. Global coverage will be further increased with the introduction of two Galileo sensor stations in Wallis (Pacific Ocean) and Bonaire (Caribbean Sea), for a total of 15 sites around the globe.
OSNMA-related metrics from January to October 2022.
G2G Development Started
Galileo’s second generation (G2G) will introduce many innovative technologies to offer unprecedented precision, robustness, and flexibility.
2022 was a key year for the evolution of G2G activities with the fast development cycles of the first batch of G2 satellites, beginning development of the associated G2G in orbit validation (IOV) ground segment and system test beds, and the consolidation of the G2G final system capabilities — including the coordination of the mission/service roadmaps with the EC, EUSPA, and the EU Member States delegates.
Ariane 62 launcher.
G2G Satellite Manufacturing
From the satellite development point of view, the two parallel contracts to develop and manufacture each of the six G2G batch one (G2SB1) satellites are progressing in a fast development environment, with the first hardware units ready for integration and testing.
Following the completion of preliminary design review, these two contracts (for six satellites each) are preparing for unit-level validation/testing, which will lead to the critical design review.
These satellites will provide the following key innovations:
Reconfigurable fully digital navigation payload
Point-to-point connection between satellites by inter-satellite-link for command and control, and ranging functionalities
Electric propulsion for orbit-raising capabilities
Advanced jamming and spoofing protection mechanisms to safeguard.
The Galileo signals will improve with:
On-board authentication capabilities
Increased ground-to-space data rate
Improved time reference (number of clocks and advanced clock monitoring functions).
G2G IOV Procurements
2022 was also the year in which two key events took place with respect to G2G in-orbit validation (IOV) ground segment and system test bed procurements:
Finalization of the procurement cycle, now in the final evaluation/award phase, to be kicked off in the first quarter of this year
Confirmation of the IOV design through different coordinated actions with the EC and EUSPA, including the G2 system preliminary design review.
The contracts will provide Europe with the following capabilities:
G2SB1 satellite launch and early orbit phase, in-orbit testing and enhanced legacy services provision
G2 new capabilities in-orbit validation, including prototyping and validation of all the novel technologies that can exploit the full capabilities of the G2SB1 satellites.
Eleven contracts will be issued to manage in synchrony all the G1 and G2 assets for the coming years:
G2 IOV ground control segment (G2 GCS) for satellites monitoring and control
G2 IOV ground mission segment/secured facility (G2 GMS-GSF) for the production, dissemination and monitoring of all enhanced legacy services and the dissemination of new G2 advanced capabilities for validation
G2 IOV security monitoring (G2 SECMON), for the cyber/security monitoring of the system
G2 filling device (G2 FD), to ensure proper initialization of system assets
G2 system test bed (G2STB), to generate and monitor new G2 capabilities for validation of the G2G mission/services
G2 PRS test bed (G2PRSTB), similar to G2 system test bed but focused on advanced PRS capabilities for validation purposes
G2 security chain (G2SC), a test bed to ensure proper satellite-ground segment qualification before launch
Four system engineering support contracts (G2 SETA), where the main GNSS technical experts from different industries in Europe provide their support to ESA and EUSPA in their different fields of expertise.
These contracts are complemented by a significant set of system research and development and test tools, such as test user receivers and radio frequency constellation simulators.
G2G batch number one (G2SB1) satellites.
Galileo Second Generation System PDR
The Galileo Programme is not only focusing on short-term G2G development activities, but also looking forward to the future in terms of the consolidation and definition of G2G final operation capabilities. During the second half of 2022, more than 200 public representatives from the EC, EUSPA, ESA and Member States held countless meetings in the frame of the G2G system preliminary design review, which concluded in early December 2022.
As part of this review, the long-term implementation (G2G in orbit capability, or IOC, and final operational capability, or FOC) was reviewed and an agreement was reached on future steps. The evolution of Galileo capabilities will not only provide better services through advanced technical solutions, but will also ensure continuity of service and enhanced backward compatibility for first-generation legacy users.
Conclusions
The efforts of ESA and EUSPA continue with the aim of providing users continuous and stable services and evolving space and ground infrastructure to maintain Galileo competitiveness with the other global navigation satellite systems.
For analogous updates on the other three GNSS constellations, please see:
The companies will combine their experience to guarantee robust and reliable navigation thanks to the Galileo constellation
The OSNMA scheme. (Image: ESA)
UAV Navigation is participating in the OSNMAplus project consortium led by Qascom, an Italian enterprise in the domain of GNSS authentication.
The OSNMAplus project aims to develop services and technologies that make use of novel services provided by Galileo, particularly use of OSNMA and I/NAV improvements.
The OSNMA service is a data authentication function for Galileo Open Service users worldwide, freely accessible to all. OSNMA provides receivers with the assurance that the received Galileo navigation message is coming from the system itself and has not been modified. The I/NAV improvements are part of a recently released update of the Galileo Interface Control Document, aiming at optimizing the navigation performance of Galileo even further.
“With the OSNMAplus project, we’re providing technological solutions that will facilitate the adoption of OSNMA in new and existing navigation systems,” said Carlo Sarto, OSNMAplus project manager. “We’re also providing cloud-based services and multiplatform SDK that can be used in consumer devices to improve the OSNMA experience and increase the robustness of the navigation solution.”
The OSNMAplus technologies will be subject to an extensive test campaign. The OSNMA-based navigation will be tested in a flying drone to assess effective resilience against potential malicious GNSS interference.
