Aircraft Gatelink Design Requirements

A commercial pilot talks to his passengers via the gatelink system.

The Airborne Communications Addressing and Reporting System is the gatelink system, which allows passengers to call home from an airplane in flight. Gatelink was an aircraft initiative during the 1990s intended to develop technology to transfer data into and from an aircraft. Aircraft gatelink design requires wireless cell phone capability with 802.11 b/g Voice over Internet Protocol (VoIP) and antennas to receive and transmit messages. Gatelink protocol transmits television images into the aircraft cabin.

Wireless VoIP 802.11g Protocol

Wireless 802.11 b/g protocol is Voice over Internet Protocol (VOIP), which transmits and communicates voice and multimedia messages through the Internet. Voice messages are transmitted as data messages with basic Hypertext Transfer Protocol (HTTP), which transmits data communications on the Internet. All the messages are sent and received with 10 basic HTTP commands to access and transmit images, data and voice communications. Since 2007, wireless VoIP 802.11 b/g protocol operates at 2.4 GHz and transfers data at the rate at 54 megabits. Wireless VoIP 802.11 b/g protocol encrypts messages for added security.

Within the Airport

Announcements of departures and arrivals are made through the gatelink system.

Gatelink used to be a higher bandwidth for air-to-ground communications. Gatelink connects an aircraft with points within an airport. Gatelink is a trust brokering communication system. Secure phones within the airport have digital identities recognized by the gatelink system. The aircraft can communicate with maintenance, baggage, ground shipping, security, ground support and ticketing. With the advent of 802.11 b/g protocol, gatelink is a wireless area network. Gatelink increases efficiency and and helps an airline stay on schedule. Gatelink also connects the pilot to the aircraft cabin. A pilot, for example, will tell his passengers via the gatelink system when the plane is readying for departure.

Antenna

An antenna on top of the airplane transmits conversations between the pilot and ground crew.

Boeing airlines participated in the development of the VoIP gatelink protocol. The gatelink wireless local area network requires an antenna 33-feet high located on top of the plane 35 feet from the nose of the aircraft. Antennas are directional or omnidirectional, radiating radio frequency waves equally in all directions. A ground-site antenna points toward the aircraft antenna with no obstructions between the two antennas. Both antennas should be roughly the same height. Each aircraft must have an access point in the VoIP system. The gatelink wireless area network will operate without a wireless signal.

In-flight Entertainment

Low-cost airline Jet Blue installed the first wireless aircraft data link. Jet Blue's data link includes a wireless gatelink in-flight television entertainment package. Jet Blue Airways offers 24 television channels transmitted to each passenger from a digital broadcast satellite. A wireless aircraft satellite unit in the cargo hold receives television images from the satellite.

References

• Aviation Magazine: Wireless Gatelink Coming of Age
• Boeing: 747-8 Ground Wireless System
• Air Transportation Association: Gatelink Airport Information Security
• ComputerWorld: Wi-Fi to Boost Data Delivery
• Air Transportation Association: Gatelink Airport Information Security
• ARINC: Aircraft/Ground Internet Protocol Communication

Resources

• ARINC: 822-1 Aircraft/Ground Internet Protocol Communication
• Cisco: Aironet 802.11A/B/G Wireless PCI Adapter
• "Journal of Small Embedded Form Factors"; Application Feature; Richard Schuh