Bringing a new but literal meaning to the term "Skynet", Google hopes to connect remote and underdeveloped areas of Africa and South East Asia to the web through a network of high-altitude blimps and balloons. The undertaking will be part of Google's broader plan to bring greater connectivity to the globe's emerging markets.
Atmospheric "base stations" floating at high altitudes have the capacity to deliver signals over large swaths of terrain – possibly dozens or even hundreds of square miles per station. Deploying a web of airborne devices would serve to increase coverage and create an armada of redundant Internet transmitters and receivers.
If Google is looking toward the sky for Internet delivery though, why not use satellites? Internet-equipped dirigibles offer a potential host of possible benefits over satellites, namely being far cheaper to deploy and offering superior latencies (i.e. better performance).
One issue Google faces though is getting Wi-Fi signals from air to ground in a coherent, end-user friendly form. If you've ever set up a 2.4GHz (or 5GHz) Wi-Fi network at home, you have likely developed an intuition for Wi-Fi's disappointing limits in terms of distance and penetration. Google's floating network would likely be miles above the surface of the Earth; so transmitting and receiving Wi-Fi signals would require prohibitively powerful and sensitive equipment on the ground.
As a result, Google has been lobbying for permission to utilize commercial airwaves below Wi-Fi frequencies. The search giant has been particularly interested in the sizeable white space (unused portion of spectrum) typically assigned to television broadcasters. These lower frequencies can be used to transmit network data across dozens of miles while simultaneously providing better penetration through objects, clouds and inclement weather. When coupled with compatible land-based transceivers, residents could use Google's airborne network as easily as watching TV or using a cell phone.
Trials have been underway in a number of locations, including South Africa. One member of the Cape Town project said Google's efforts to deliver Internet access to educational facilities have "gone really, really well."