Helium balloons of the future network that should give Internet to everyone in the world fortunately use ADS-B.
If you point your browser to Flightradar24.com and zoom off the coast of New Zealand, you’ll see 7 slow moving aircraft: these are actually helium balloons, part of Google’s Project Loon, broadcasting their position, speed, altitude etc. via Mode-S ADS-B.
Project Loon is a research and development project whose aim is to provide Internet access to everyone, even if they live in rural and remote areas. The project features high-altitude balloons, made from sheets of polyethiylene plastic and measuring 15×12 meters, placed in the stratosphere at an altitude of about 20 mi (32 km) with the purpose of crating an aerial wireless network with up to 3G-like speeds.
The helium balloons are all “floating” around 1,000 feet to the southeast of New Zealand, and a probably involved in a testing campaign; after the trial (kicked off in June 2013) Google hopes to launch thousands of balloons around Earth to provide global Internet access.
In the wake of Snowden scandal, someone said that the purpose of the project may not be philantropic and the task of the network of balloons would be global communications monitoring. But this is another story.
Top: Flightradar24.com screenshot