Civil-military communications interoperability
The ground communications infrastructure supporting civil-military ATM exchanges varies from State to State but normally comprises switched or direct lines for inter-centre voice and flight data (On-Line Data Interchange - OLDI) coordination as well as connections supporting radar data exchanges. In addition, Air Navigation Service Providers (ANSPs) normally make available ICAO Aeronautical Fixed Telecommunications Network (AFTN) connectivity or remote terminals which are used to exchange flight plans, NOTAMS (Notices to Airmen), meteorological data and other aeronautical information.
The ground communications interoperability challenges include:
- the need to enhance data exchanges in line with the widespread use of Internet Protocol networks (including the Pan European Network Service (PENS));
- the advent of a new messaging system to replace AFTN: Aeronautical Message Handling System (AMHS); and
- the introduction of initial network-centric structures such as System Wide Information Management (SWIM).
In terms of air-ground voice requirements, military aircraft equipped with Very High Frequency (VHF) transceivers with 8.33 kHz channel spacing are interoperable with the infrastructure operated by civil ANSPs. Nevertheless, non-8.33 State aircraft are accommodated with Ultra-High Frequency (UHF) when provided by those ANSPs or by VHF 25 kHz channels.
Scenario for the years to come
The introduction of air-ground data link communications to support advanced concepts will be the main technological evolution in the years to come.
The deployment of Controller Pilot Data Link Communications (CPDLC) will impact transport-type State aircraft.
Further developments will follow to sustain other requirements such as 4D trajectory management. While the initial capabilities rely on the ATN/VDL (Aeronautical Telecommunication(s) Network/Voice Data Link) Mode 2 infrastructure, higher capacity data links (future COM) will be introduced to enable more demanding requirements.