Wireless carriers have spent millions of dollars and years for preparing for one day. Which makes sense when that single day is the 2019 Super Bowl.

The carriers have installed hundreds of new antennas and small cells (think mini cellular towers) in and around Mercedes-Benz Stadium in Atlanta to increase the capacity of the network for the more than 1 million fans expected to come to town to root on either the New England Patriots or the Los Angeles Rams at the game on Sunday.

While the football fans won't be staying, many of the upgrades are permanent and will be used in 5G network upgrades. The next wave of wireless, 5G promises faster speeds and quicker network response times for new services like streaming VR and self-driving cars.

Sprint

Because 5G builds on 4G foundational technologies, carriers will be able to reuse this gear when it's time to light up the next wireless generation simply by upgrading the software.

"We want to deliver a great network experience, whether customers are sharing their favorite moments on social media, making a call or checking email," said Scott Mair, president of AT&T Operations. "Many of the network enhancements deployed for the big game are permanent and will continue to benefit customers and first responders long after the game ends."

As fans send selfies and share videos on social media, the volume of traffic on the nation's four biggest carriers is once again expected to hit records, topping last year's tsunami of data. At the game in 2018, usage included Verizon's reported 18.8 terabytes of data flowing through its network during the game inside the stadium; AT&T's 7.2 TB of data, and Sprint's 9.7 TB of data both inside and outside the stadium.

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In order to handle all this traffic, carriers have been upgrading their networks both inside the stadium and throughout Atlanta, including Hartsfield-Jackson Atlanta International Airport, as well as popular tourist areas like Centennial Olympic Park.

Here's a look at what each of the carriers is doing this year for the big game.

AT&T

In total, AT&T says it's spent $43 million to upgrade its network in Atlanta. It's also the first carrier to make standards-based mobile 5G available in Atlanta.

"Bringing mobile 5G to parts of Atlanta ahead of this year's Big Game was a priority for us," the company said in a press release.

Here are some of the highlights of that investment.

1,500 antennas and 1,550 remote amplifiers to Mercedes-Benz stadium.



300 percent more LTE capacity since the start of the 2018 football season.



New Distributed Antenna System (DAS) at 30 additional locations throughout the Atlanta area to boost capacity of the LTE network.



The launch of the FirstNet public safety network to provide coverage and capacity for first responders.



Verizon

Verizon says it's spent $97 million on upgrades to get ready for the 2019 Super Bowl. Here's some of what it's done.

Installed 350+ miles of fiber throughout Atlanta



Installed close to 30 new permanent cell sites



Installed 300+ permanent small cells



Added additional capacity in close to 150 existing cell sites



Added capacity to the DAS system at Hartsfield Jackson



Upgraded DAS system within stadium



Upgraded Wi-Fi system to allow for seamless access for additional capacity.



Deployed antenna technology under seats to boost capacity



T-Mobile

T-Mobile says it's boosted capacity by eight times in key locations in preparation for the Super Bowl.

Upgraded cell sites where the biggest crowds are expected, including Mercedes-Benz Stadium, Hartsfield-Jackson Atlanta International Airport, as well as key hotels throughout the city, along transit routes and at dozens of Super Bowl event venues like Cobb Galleria, Centennial Olympic Park, Georgia World Congress Center and State Farm Arena.



Upgraded to the highest-capacity DAS on T-Mobile's network in the stadium, with 50 percent more capacity than the next largest stadium.



Added the first outdoor C-RAN system in the tailgating and events areas. A C-RAN is a cloud-based radio access network that improves network performance in high-traffic scenarios and can even extend the battery life on smartphones, according to T-Mobile.



Added more than 300 small cells and 20 new DAS at key venues to enhance indoor coverage.



Doubled LTE capacity at SunTrust Park and enhanced the network throughout midtown, downtown and around the stadium and tailgate areas.



Sprint

Sprint says that it's spent "millions of dollars over the last two years" building its "next-gen network" in Atlanta and that it's installed the equivalent of seven cell sites worth of equipment serving Mercedes-Benz Stadium. To put that in context, Sprint said that's the same number of cell sites that are used to cover a small city on a normal day.

Here are some of the specific upgrades the company is touting.

Upgraded hundreds existing metro Atlanta cell sites to use all of Sprint's available bands of spectrum – 800 MHz, 1.9 GHz and 2.5 GHz – to improve speed and reliability of service.



Installed hundreds of small cells on infrastructure like telephone poles and streetlights to help "fill in" areas of the network.



Deployed 5G Massive MIMO technology to increase 4G LTE capacity up to 10 times, giving customers faster data speeds in high-traffic locations like downtown and around the stadium. Sprint says the radios can easily be upgraded via software to lay the foundation for Sprint's mobile 5G service, which is expected to launch in Atlanta in the first half of 2019.



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