Preparing for the Galileo Commercial Service – Proof of Concept and Demonstrator Development (2014)

According to the Galileo Mission Requirements, the Galileo Commercial Service (CS) will provide an added value with respect to the Galileo Open Service and other GNSS signals. The European Commission is currently working together with the European GNSS Agency and with the European Space Agency, with the support of Member States, on the strategy that will lead to the provision of an operational Commercial Service, and on its associated exploitation model, for the following years. Without precluding the provision of other services in the future, the main services foreseen to be part of the CS are authentication, understood as the ability of the system to guarantee the users that they are utilizing signals coming from the Galileo satellites and not from any other source, and high accuracy, that is, the ability of the system to provide a positioning accuracy in the order of a few centimeters.

At the end of 2013, a consortium led by GMV was awarded with a contract for the development and operational validation of the CS Demonstrator, which represents a fundamental step in the European Commission’s strategy for the deployment of the CS and a key element to make the CS a complete success. The CS Demonstrator is introduced in the overall strategy with a twofold purpose. On the first hand, to enable a CS proof of concept, allowing the testing of its functionalities and the evaluation of its potential performance in simulated and real environments, including the broadcast of the CS signals through the Galileo satellites and CS signal reception in a receiver. On the second hand, to offer to potential CS Providers a platform where to test and validate new services that they may offer to the GNSS user community

The Galileo CS signal is the first commercially available GNSS signal that will provide the capability of signal authentication for civilian uses. The CS allows the implementation of both signal and data level schemes. Signal level encryption refers to the encryption of the ranging codes, which limits the access to users that do not have access to the keys and supporting hardware. The CS allows the encryption on both E6B and E6C channels. Data level authentication allows the implementation of Navigation Message Authentication (NMA), that is, authentication of the navigation data, including timing and orbit information. NMA does not limit the signal access, and therefore allows the deployment of open radio navigation services to all users, while enabling users that have access to the NMA service to authenticate the signal. The use of encrypted signals allows the exploitation of new services based on assistance channels, which allows the deployment of Remote Processing Authentication (RPA) or Signal Authentication Sequences (SAS) techniques. These techniques do not require storage of cryptographic keys on the receiver and are based on the interaction with a remote Authentication Server. Their use in the CS demonstrator is currently under investigation. The investigation of different techniques aims to provide different services, fulfilling different security and cost requirements 

Once the CS Demonstrator platform is fully developed, integrated and validated, it will be deployed and operated for testing activities, with the objective to demonstrate the CS functionalities and potential performances. The CS Demonstrator will be able to run in real environments by interacting with the Galileo Core Infrastructure, receiving information needed for the generation of the CS messages and transmitting the messages to be broadcast through the Galileo satellites.

The scheduled test campaign will encompass three phases. The first step was intended to support the declaration of a Galileo CS Early Service proof-of-concept at the time of the Galileo Early Services declaration, which was initially foreseen by October 2014. During this phase, the interface with the system is based on the provision of off-line data that is later transmitted through E6 signals at certain weekly slots; this allows testing the reception of E6-B/C signals, and analyzing the achievable performances of future potential services. The real-time tests of the second phase will start once the CS Demonstrator platform has been successfully integrated with the GNSS Service Centre, thus being ready for real-time transmissions. In this case, the CS data transmissions will be based on the CS data generated with the algorithms implemented in the CS Demonstrator platform for Authentication and with GMV’s magicGNSS products for High Accuracy. During the last testing phase, CS data transmissions will be based on the CS data supplied by CS Providers willing to participate in the test campaign.

In conclusion, the CS Demonstrator will build the basis for the experimentation and assessment activities needed for the consolidation of the authentication service definition, for the optimization of the Galileo CS signal structure in terms of bandwidth allocation for different service providers, for the definition of the CS user terminal requirements, for the consolidation of the CS signal-in-space interface, and for the definition of the interface between CS providers and the GNSS Service Centre, which is the gateway to the Galileo Core Infrastructure. The test campaign that will be performed with the CS Demonstrator will allow analyzing the service functionalities and performance and supporting the development of the technologies needed for future applications based on the Galileo CS.

The objective of this paper is to present the CS Demonstrator (architecture and operational modes) and its role in the roadmap to the Galileo CS; and to address the different authentication solutions that will be defined and implemented. The paper will also describe the planned test campaign, which has allowed the testing of the Galileo CS functionalities and the evaluation of its potential performance in simulated and real environments, including the broadcast of the CS signals through the Galileo satellites and CS signal reception in a receiver. Finally, the strategy to offer to potential CS Providers a platform where to test and validate new services that they may offer to the GNSS user community will be presented.