CNS Infrastructure and Services

The CNS domain evolutions will be driven by a service-based approach and a performance-based approach. This will enable the de-coupling of CNS service provision from air traffic services, ATM data services. This change will lead the European ATM system to be more flexible and resilient, allowing scalability.
Through a service-based approach, the CNS services will be specified through contractual relationships between customers and providers with clearly defined, European-wide harmonised services and level of quality. This approach will create business opportunities for affordable services with a strong incentive for service providers to compete resulting in cost-efficient services. The progressive introduction of a CNS service-based approach will enable the virtualisation of ATM (consisting in decoupling the provision of ATM data services from ATS) and will enable ANSPs to make implementation choices on how new services are provided. A CNS service-based approach (as illustrated in figure 12) should provide a strong incentive for service providers to cooperate across national boundaries, to optimise the use of technologies as well as the geographical distribution of equipment (and hence optimise spectrum use). It will also provide a better environment for the integration of new CNS services – such as space-based automatic dependent surveillance broadcast (ADS-B) and satellite communications.
The performance-based CNS approach sees an evolution from system/technology-based operations, where systems/technologies are prescribed, towards the delivery of performances-based services, which specify the ambition to be achieved within a specific environment.
It is anticipated that this service-based and performance-based approach will favour potential technological/functional synergies across the communication (COM), navigation (NAV) and surveillance (SUR) domains, taking advantage of common system/infrastructure capabilities for the ground, airborne and space segments. From a service standpoint the boundaries between the different domains will disappear progressively as the infrastructure moves to an integrated “digital” framework. It will be the most cost effective for the providers and users. Technologies will evolve over time without requiring the operations themselves to be revisited, as long as the requisite performance is provided by the system.
The future CNS infrastructure will be based on an integrated CNS backbone comprising multi-link pan-European network service (PENS), global navigation satellite system (GNSS) and ADS-B. This integrated backbone will be complemented by a minimum operating network (MON) , composed of legacy infrastructure systems (e.g. distance measuring equipment - DME, instrument landing system - ILS), rationalised to provide efficient support and operate as a back-up for the integrated backbone. During the transition towards the SESAR vision, the degree of rationalisation will increase along with the development of CNS services.
With this approach, the introduction of new capabilities follows an integrated CNS roadmap, which provides robustness and new opportunities to enable performance-based and service-based CNS and facilitate air traffic services while ensuring civil/military interoperability.
Performance requirements can be expressed with respect to various airspace user types and various environments, while aiming at optimising the overall performance with no degradation related to the least capable airspace user(s).
The EU strategies and policies for Europe (COM (2016) 705) and (EU) 2018/1139 Regulation, with respect to space-related technologies, encourage the uptake of solutions that are enabled by EGNOS and Galileo. In this respect, the EU Air Navigation Strategy (2018) developed by the EC and presented to the Single Sky Committee (SSC) in the context of performance-based navigation (PBN) implementation roadmap, confirms the availability of PBN applications as from 2015. It states that, in order to ensure necessary independence when GNSS is the primary means of navigation, Galileo and EGNOS will become GNSS components required in the EU, for the multi-frequency, multi-constellation GNSS system.
For end users, the technological solutions will be packaged or merged in a way that guarantees availability, integrity, safety and security and performance requirements, mandated by relevant authorities.