Duke’s One-of-a-Kind Cellular Network System

By Viraaj Punia, '22
OIT Communications Intern

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Have you ever wondered how Duke has good cellphone reception for all major carriers? Or how you rarely lose signal on campus even if you’re in a large stone building, yet there aren’t cell towers strewn all over campus? How is this possible?

In 2013, Duke’s Office of Information Technology (OIT) set in motion a groundbreaking deal that had never been seen before at universities – a distributed antenna system (DAS) that boosts cell signal in buildings over 20,000 sq ft. And the cellular carriers AT&T, Verizon, and Sprint pay for it. T-Mobile is joining later this year.

According to John Andreala, OIT’s Director of Physical Infrastructure & Operations, “Duke could be the only school in the country to have a neutral hosted [Duke-owned] DAS fully funded by the carriers, with maintenance also fully funded.”

Having a neutral hosted system is important – this way all carriers share one infrastructure, instead of requiring a separate setup for each carrier. For instance, when implementing 5G in the future, it would be terrible to have numerous antennae for each carrier rather than being able to use the same antennae for all carriers. Due to this innovation, each carrier has the equivalent of 12 macro-cell towers on the shared infrastructure.

Now this might seem like some technical jargon-filled complexity that doesn’t really apply to the average person at Duke, but maintaining strong cell coverage for the three largest carriers benefits everyone. We don’t have to think twice about where we are to make a call, send a text, or to use cellular data if the WiFi is down.

Duke is continually innovating its network infrastructure. According to John Robinson, OIT’s Director of Network Engineering, “we have a proof of concept/pilot running on campus to evaluate private LTE – a next generation wireless platform.” Private LTE would consist of a Duke-only network that provides more comprehensive outdoor coverage and is more secure than WiFi, since LTE and cell networks are regulated by the FCC.

In fact, Duke’s efforts in higher education network infrastructure made news recently when it was announced that Duke is partnering with DISH Wireless and CISCO to pilot a neutral host network for higher education institutions using Citizen’s Broadband Radio Service (CBRS), a shared spectrum. 

5G, the new high-speed cellular network standard, is also another area where Duke wants to expand. Verizon and other networks are looking to deploy 5G by Wallace Wade and Cameron Indoor stadiums, since those are areas with high outdoor traffic. The DAS system already has big trailers housing some of its infrastructure by the Blue Zone parking area, as well as antennas on almost every floor of most buildings.

According to Bob Johnson, OIT’s Senior Director of Communications Infrastructure and Global Strategies, “we are just now starting to build 5G infrastructure, but getting it done depends on how much the carriers are willing to invest on campus. The most expensive part is laying the fiber optic cable.”

Fast WiFi and strong cell coverage are things we take for granted at Duke, but there is so much that goes on behind the scenes to make these a reality. We might not notice these technologies explicitly, but the network and infrastructure teams continue to push the boundaries of wireless connectivity at Duke.