Mobile Communications On-board Aircraft

Definition
Mobile Communications On-board Aircraft (MCA) technology is identical to normal mobile roaming in that airline passengers are billed through their service provider. The tariffs applied usually correspond to "Roaming: rest of the world" prices. Wi-Fi is also used for MCA but is not subject to specific rules because its low power does not pose interference risk with ground-based radio services.

MCA does not cover the communication between the aircraft and the ground which is currently provided by satellite-based systems. New satellites should allow ten times greater capacity than what is available today.

How the MCA system works
The signal is received by an antenna on board the aircraft and sent to the ground network via a satellite connection. The signal is limited in power to ensure it does not interference with other communications.

The system is based on three main parts: the mobile terminals, the Network Control Unit, and the aircraft base station.


 * Mobile terminals on aircraft: passengers increasingly wish to use their 3G or 4G mobile devices (smartphones, tablets, laptops etc.) on board aircraft to transfer data; the amount of data transferred on board already exceeds voice data.
 * Network Control Unit (NCU): is mounted on board the aircraft and is a kind of jammer which prevents mobile terminals connecting to, and interfering with ground-based systems, and ensure they connect only to an Aircraft Base Station.
 * Aircraft base station: the antenna to which mobile terminals connect; it takes the form of a cable running along the ceiling of the cabin.