A world of millimeter-wave networks, laid out by computer, crisscrossing cities and into the stratosphere, where cell phone towers can be easily replaced by tethered autonomous copters—that’s the telecommunications infrastructure of the future. So says Facebook’s Yael Maguire, head of the company’s Connectivity Lab.
Speaking at Facebook’s F8 developer conference in San Jose today, Maguire said that Facebook is aiming to bring down the cost of connecting by an order of magnitude, working to develop the building blocks of more flexible and extensible networks.
A big part of that strategy, he said, is millimeter wave communications. Near term, he says, are millimeter wave networks connecting cities, a simpler route to high capacity communications than extending fiber optic networks to every building. The company’s project here is called Terragraph; it is, Maguire said, “designed to be consumer level in pricing and deployed by mobile operators.”
Facebook’s real secret sauce in city-level millimeter wave communications, Maguire explained, is its use of computer vision and artificial intelligence to analyze a city and determine possible paths for communications. It has also, he said, developed new technology for rerouting these networks when communications are interrupted, and is currently testing this technology in San Jose.
Further out are Facebook’s efforts to use its Aquila aircraft in the stratosphere to allow long-distance communications. In recent tests, Facebook engineers clocked 36 Gbps of data transfer over 13 km using a stationary millimeter-wave link and 16 Gbps of data transfer from the ground to a Cessna aircraft; the Cessna acted as a stand-in for the futuristic Aquila. Maguire admitted it could take 10 years before this communications technology becomes practical. (Facebook also achievedand 80 Gbps using an optical link to the Cessna.)
Nearer term for connectivity in rural areas, he said, is reducing the cell-phone tower to what Maguire calls its absolute essence: the Tether-tenna. He described this as a cable tethered to ground-based power and fiber optic networks, held up by an autonomous ultralight helicopter. There are a few things to work out, he said, “it’s a high voltage system, it has to survive high winds and lightning.” In tests, he reported, the Tether-tenna has run for 24 hours; the company expects to extend that to months.
Maguire also said the company is particularly interested in using its technology to create instant infrastructure for use in a crisis; long term, Aquila will be able to be fill that niche, but he sees Tether-tenna as also being useful—and just a few years away from implementation.
Tekla S. Perry is a senior editor at IEEE Spectrum. Based in Palo Alto, Calif., she's been covering the people, companies, and technology that make Silicon Valley a special place for more than 40 years. An IEEE member, she holds a bachelor's degree in journalism from Michigan State University.