In-flight Internet
Kartavya Desk Staff
Source: TH
Subject: Science and Technology
Context: With rising global air travel, in-flight Internet has become a standard service on commercial flights, prompting renewed public interest in how aircraft stay connected mid-air.
About In-flight Internet:
What It Is?
• In-flight Internet refers to wireless Internet access provided to passengers on aircraft, using onboard Wi-Fi networks that relay data to the ground through specialised aviation communication systems.
Types of In-flight Internet Systems:
• Air-to-Ground (ATG) Systems: Aircraft connect to ground-based towers with upward-facing antennas, similar to cellular networks, making coverage effective over land.
• Satellite-based Systems: Aircraft use dome-mounted antennas to link with geostationary (GEO) or low-earth orbit (LEO) satellites, enabling connectivity over oceans, deserts, and polar regions.
How it works?
• Your device joins a local wireless network inside the aircraft, which is distributed through multiple ceiling-mounted access points to ensure stable connectivity across the cabin.
• All passenger data flows to a core onboard server that processes requests and directs them either to the air-to-ground antenna or satellite terminal, depending on the system in use.
• The aircraft’s antenna maintains a continuous radio link with ground towers or satellites, transmitting packets outward while receiving return traffic for onboard users.
• In satellite-based systems, orbiting GEO or LEO satellites act as intermediaries, bouncing data between the aircraft and ground teleport stations linked to fibre Internet networks.
• Once connected, passengers are routed through a browser login page where the system verifies identity, enforces usage policies, and prioritises limited bandwidth across the aircraft.
Key Features:
• Continuous connectivity even at 30,000+ feet using certified aviation hardware.
• GEO satellites provide wide coverage; LEO constellations offer lower latency and higher speeds.
• Dynamic bandwidth allocation across multiple aircraft.
• Onboard traffic shaping—blocking VoIP calls, compressing images, limiting streaming.
• Multiple Wi-Fi access points ensure cabin-wide signal distribution.
Limitations:
• Bandwidth constraints: Total data is shared by all passengers; speeds drop when many users are active.
• Latency issues: GEO satellites (~36,000 km above Earth) cause delays of 500–700 ms.
• Network variability: Routes, weather, satellite load, and provider quality affect performance.
• High cost: Aircraft antennas, modems, and bandwidth leases are expensive for airlines.