Facebook Targets Wireless Broadband

Its multi-node ‘Terragraph’ system designed for 60-GHz spectrum
Facebook terragraph network.jpg

In a move that should draw the attention of incumbent ISPs and mobile service providers, Facebook, said its Connectivity Lab is pushing ahead with a plan to use emerging millimeter wave technology to drive speedy wireless broadband services to dense urban areas.

That system, called “Terragraph,” is being billed as a 60-GHz, multi-node system that will use off-the-shelf components and tap into the proverbial cloud “for intensive data processing,” Facebook described here. Terragraph, Facebook said, will use radios that are based on WiGig, an enhancement to the WiFi standard for in-room, high-bandwidth communications.

“Combined with Wi-Fi access points, Terragraph is one of the lowest cost solutions to achieve 100 percent street-level coverage of gigabit Wi-Fi,” Facebook said.

Facebook is testing it at the company’s Menlo Park, Calif., headquarters and expects to expand to a broader trial in nearby San Jose later this year, Facebook engineering VP Jay Parikh said at the company’s F8 developers conference, according to DSL Reports.

Per an announcement from Facebook and the city, the test system, to be deployed in downtown San Jose in late 2016, will culminate in an “open, publicly accessible, gigabit-speed outdoor WiFi network.”  They’re also exploring plans to bring it to “underserved” San Jose neighborhoods and “transit innovation corridors.”

 Facebook will provide the hardware and software for Terragraph, and the city will open access to streetlights and other infrastructure needed for the network build-out.

Facebook’s approach with Terragraph appears to shares some similarities with Starry, a startup led by Chet Kanojia, founder of now-defunct pay TV industry disrupter Aereo, that intends to offer alternative gigabit broadband services that also rely on millimeter wave technology.

To deal with the limited range of 60 GHz technology, the plan is to deploy nodes in a city at intervals of 200 meters to 250 meters, and the use of an architecture that can route and steer signals around tall buildings that block signals.

“Although 60 GHz has traditionally been avoided due to its high absorption of oxygen and water, countries such as the United States, United Kingdom, Germany, China, South Korea, Japan, and others saw the benefit of making this part of the spectrum — also known as “V-band” — unlicensed, similar to the Wi-Fi 2.4 GHz and 5 GHz bands,” Facebook said.

Facebook also talked up the development of Project ARIES (Antenna Radio Integration for Efficiency in Spectrum),  a base station with 96 antennas that, the company claims, can support 24 streams simultaneously over the same radio spectrum. Facebook said it’s conducting that work amid the progress toward 5G technology and the notion of “Massive MIMO” systems that utilize a large number of antennas.

“ARIES is an embodiment of such a technology — by using the notion of “spatial multiplexing,” the antenna array at the base station can serve a multiplicity of autonomous user terminals on the same time-frequency resource,” Facebook said.

This spatial resource sharing policy, it added, can serve as an alternative to the need for spectrum licensing, but also the procurement of more base stations required by high-density, small cell deployments.