The objective of the GMCA was to provide a basis upon which Galileo can be relied upon to the same extent that GPS is currently by the aviation user community.
Satellite navigation provides continuous, real-time, reliable, accurate and globally available position, velocity and time. The technology fits important societal and market needs. The European aviation community relies heavily on GNSS and is working towards multi-constellation and multi-frequency solutions to enable a more efficient operational environment.
The aviation community has confidence in GPS and EGNOS, backed up by many years of study, data-collection and experience. Such confidence in new technologies like Galileo has yet to be established. Historically this community has been reluctant to accept new technologies and slow to adopt them.
To derive full benefits of Galileo for the aviation community as early as possible, it is crucial to gain a better understanding of what it has to offer. This includes the operational community (Civil Aviation Authorities (CAAs), Air Navigation Service Providers (ANSPs), etc).
The ICAO offers guidance in its Annex 10 relating to the use of GNSS (Chapter 2 of Volume I, paragraphs 2.1.4.2 and 2.3.1 respectively):
(a) A State that approves GNSS-based operations should ensure that GNSS data relevant to those operations are recorded. These recorded data are primarily intended for use in accident and incident investigations. They may also support periodic confirmation that accuracy, integrity, continuity and availability are maintained within the limits required for the operations approved.
(b) Aerodrome control towers and units providing approach control service shall be provided with information on the operational status of radio navigation services essential for approach, landing and take-off at the aerodrome(s) with which they are concerned, on a timely basis consistent with the use of the service(s) involved.
Regulatory authorities around the world base their regulations and approvals on Annex 10 or their own operational imperatives.
DW International (DWI) developed a GNSS Performance Monitoring System (GPMS) for airports and ANSPs in order to meet the ICAO guidance and state regulations. It allowed users to monitor and record GPS signal data at airports. Prior to the GMCA project however it did not have capability of monitoring and recording Galileo signal data. Enhancing the system to include Galileo provides users with the means to meet guidance and regulations when they start to approve Galileo-based operations. Therefore, the GMCA promotes the adoption of Galileo-based procedures when they start to be implemented. Though the system was originally intended for the aviation domain, it can be deployed in other environments where GNSS monitoring is required.
In parallel to the developments described above, greater attention is being focussed on the issue of GNSS vulnerabilities: interference, jamming, spoofing, meaconing etc. As these issues tend to be localised, the addition of detection capability to the system was deemed to be of value to users. If users can be alerted to instances of interference then they can react accordingly in order to alert their airspace users. Qascom and Chronos Technology Ltd (Chronos) had already developed sensors which can identify instances of interference affecting GPS so the GMCA was an opportunity for them to upgrade their sensors in order to be able to detect interference related to the Galileo signal. Qascom updated their SMART Sensor so that it could identify instances of spoofing and meaconing of Galileo signals; Chronos updated their existing GPS-only jamming and interference detection sensors to include Galileo.
