What is Terragraph?

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- everything RF

Mar 8, 2019

Terragraph, is a project started by facebook to reduce the time and cost for service providers to deploy high speed connectivity through the use of millimeter wave technology. It is a 60 GHz multi-hop multi-point wireless network that delivers gigabit speeds in dense urban areas. The aim of the project is to create a mm-Wave wireless network within a city and to deliver fiber-like connectivity at a lower cost than fiber. 

Terragraph radios are based on the WiGig standard and can be deployed on street poles or rooftops.

The Terragraph network operates in the unlicensed 60 GHz 'V' band and uses the cloud for intensive data processing and self-organization. The 60 GHz band has over 7 GHz of bandwidth available for use (some countries like US are even expanding it to 14 GHz), making it the largest commercial radio band ever used.

The technology employs a TDD/TDMA MAC structure which enables extremely efficient use of this spectrum even in highly congested scenarios. The radios are able to inter-connect to form a Layer 3 mesh which can be scaled over large geographic areas and provides redundant and reliable connectivity between end-points.

Terragraph radio nodes can be deployed on a number of physical assets such as street furniture to provide last-mile gigabit-per-second connectivity between a service provider’s fiber presence and subscriber residences. The deployment of street-level radios mitigates the high costs associated with running fiber to every street corner, thus lowering the cost-barrier for service providers to bridge the demand for high speed connectivity.

Key Features of Terragraph:

  • Operates in the unlicensed V-band: 60 GHz
  • Uses standardized 802.11ad and 802.11ay, enhanced with TDD/TMDA for MAC efficiency at scale
  • Current proof-of-concept system has a peak data rate of 4.6 Gbps (one direction) and average peak user throughput of over 1 Gbps
  • Single link maximum range is approximately 250 meters
  • The network can be deployed in days rather than months
  • Highly cost effective vs buried fiber
  • Small, lightweight and low power - suitable for street level deployments
  • Supports highly scalable layer-3 mesh, powered by Open/Routing software
  • Uses IPv6