Military Avionics Systems

7Communications and Identification

7.1 Definition of CNI

All military aircraft need certain computing sensing and computing resources apart from the mission sensors and weapons to enable them to complete their mission. These are:

1. Communications. The ability to be able to communicate by either voice or data link means with cooperative forces, be it wingmen in the same flight of aircraft, airborne command centre or troops on the ground.
2. Navigation. The military platform needs to be able to navigate with sufficient accuracy to a target, rendezvous point, waypoint, or initial point as dictated by the mission requirements.
3. Identification. The rules of engagement for a given theatre of operation will necessitate the classification and identification of a target before permission to engage is given.

The American military refer to this collection of resources as communications, navigation, identification (CNI).

Some of the CNI sensors such as air data, radar altimeters and inertial systems are autonomous to the platform, in other words the platform needs no other input from third-party sources. Others such as communications, radio navigation beacons and global navigation satellite systems (GNSSs) require the participation of other organisations to respond or the provision of a network of aids or a constellation of satellites to provide the navigational framework. Military platforms use a combination of all these sensors with the additional rider that, for certain covert stages of ...