Monday, 3 July 2017
Planes used to be WiFi-free zones, but not any more. Now, you can send and receive e-mails, keep your Facebook page up-to-date or stream movies while soaring through the air.
Access to WiFi comes at a cost, of course, and the damage to your wallet will depend on the connection speed and how long you want to stay online.
But how does WiFi work when you’re tens of thousands of feet above the ground? It’s all to do with geostationary satellites, according to Stefan Barck, a technician for Lufthansa.
Satellites in geostationary orbit (about 30,000 kilometres above the earth) send and receive signals via receivers and transmitters.
The aircraft antenna is mounted on the fuselage, creating a link to the nearest satellite. The signals are initially passed to a server on the aircraft, which then distributes them to so-called wireless access points.
This translates into full Internet access for passengers who want to use their tablets, smartphones and laptops during the flight.
Some systems allow passengers to be online throughout their time on board, including take-off and landing, while others can only be used above 10,000 feet – flights tend to cruise at above 35,000 feet (10,500 metres).
The best connection is achieved in cloudless conditions or when flying above the clouds. “Then there are no disruptive factors, such as water droplets, which can affect the signal,” Barck says.
Source by: Internet