When cruising at an altitude of 10,000 meters, how does in-flight Wi-Fi technology actually work?

Currently, there are two primary methods to enable internet access in the air. The first involves installing an antenna on the aircraft’s exterior to connect with communication satellites. However, this approach suffers from higher latency and involves elevated equipment and maintenance costs.

The second method is Air-to-Ground (ATG) communication.

The technical architecture of ATG is not overly complex. Taking 5G ATG as an example, telecom operators deploy 5G-ATG base stations along flight routes, while aircraft are equipped with specialized antennas, CPE (Customer Premise Equipment), and onboard Wi-Fi or other networking devices.

Signals from ground-based base stations are captured by the aircraft’s antenna and transmitted into the cabin. The CPE onboard then converts these signals into Wi-Fi, enabling two-way communication between the aircraft and the ground.

While this may sound straightforward, delivering high-speed, stable connectivity is no easy feat.

Due to the aircraft’s extreme velocity, ATG base stations must cover a far wider radius than terrestrial ones—up to 300 km—to maintain connectivity. Additionally, the aircraft’s rapid movement causes shifts in signal frequency that can exceed a base station’s recognition range, requiring advanced algorithms to correct these deviations.

Beyond building the ground infrastructure, aircraft themselves must undergo ATG system modifications. These upgrades must prioritize safety while enabling seamless connectivity.

The benefits of ATG extend far beyond passenger convenience. It enables critical data transmission from the cockpit, real-time communication with ground control, and even remote medical assistance during emergencies such as onboard health crises.

In the future, in-flight internet access is poised to become even more widespread and user-friendly.