Radio-electrical equipment for air transport provides links between different aircraft (in-flight anti-collision systems), between aircraft and ground and also inside a single aircraft. It is conducive to greater in-flight safety and regularity. Since development costs are high for such equipment, a degree of regulatory stability is recommendable.
The aeronautical sector is of strategic importance for the French economy. French companies operating in this sector (designers of commercial and business aircraft, helicopter designers, avionics and radar manufacturers, satellite constructors and operators) are world leaders in their respective fields, in civilian and defence applications alike. Their contribution to aeronautical safety worldwide is significant.
The SESAR programme (Single European Sky ATM Research), the technological section of the “Single European Sky” (SES) initiative, aims to modernise systems and infrastructures used for Air Traffic Management (ATM) so as to facilitate the reorganisation of European airspace and meet essential requirements for the sustainable development of air transport as regards safety, the environment, capacity and economic efficiency.
For air transport, spectrum use includes air-to-ground, navigation and surveillance communications. There are a number of very different applications for use in radiodetermination (radars) as well as in voice and data transmission, by direct links or via satellites.
HF and VHF bands are used for voice and data communications over long and medium range and also for radio beacons and landing aids.
Bands just above 1 GHz are exploited extensively to determine aircraft distances (DME), for secondary radars (SSR), anti-collision systems (ACAS) and the aircraft tracking system (ADS-B). The future aeronautical communication system (LDACS) is also in the process of development in this band.
The 5 GHz band (5030-5150 MHz) was initially set aside for an improved mobile landing system (MLS). Now, however, it is mainly being considered for other developments, in particular direct or satellite communication systems, as well as communications for drone command and control, for aircraft on the ground and for the Airbus aeronautical telemetry system.
A large number of bands are widely used for ground and airborne radars. Each frequency is assigned to a different specific purpose. The 1.3 GHz band is used for long-range primary radars, while the 2.8 GHz band is preferred for medium-range radars. Motion-sensing ground-based radars use the 9 GHz and 15 GHz bands. Onboard radars are on the 4.3 GHz band (altimeters) and the 5.3 GHz and 9 GHz bands (weather radars).
Forthcoming innovation in the air transport sector will require appropriate spectrum resources. Manufacturers of commercial aircraft (including Airbus) are developing wireless connections (WAIC/Wireless Avionic Intra Communication) to replace some of the wiring needed to pilot an aircraft. Equipment of this kind will probably be appearing on the market by 2019. WRC-15 concluded that the portion of the spectrum reserved for altimeters could be shared with these new applications.