More than 1 million travelers passing through Denver International Airport over the long holiday weekend will experience better cellular service than nearly anywhere else in Denver. Then they’ll board their planes and leave the city or return to their Denver neighborhood where subpar mobile service is the norm.
This is because in a city that ranks as one of the worst nationwide for cellular service, every major mobile carrier has beefed up the number of antennas at DIA so more people can get a good signal and decent data speeds during the busy travel season, which the airport expects to be busier than last Thanksgiving holiday.
“Airport upgrades should be up and running” by Tuesday afternoon and are permanent, Suzanne Trantow, a Denver-based AT&T spokeswoman, said in an email. She added that the latest improvements offer 80 percent more LTE capacity at the airport.
Those enhancements include indoor antennas called DAS, or a distributed antenna system, which are small antennas spread throughout the airport. It’s a way to improve the signal inside buildings where outdoor cell towers can’t reach. And while the signal is technically only as good as what AT&T or another mobile carrier provides elsewhere in Denver, the technology is so targeted to a location that reception and data speeds are much more consistent than in areas without enough antennas, especially in neighborhoods where residents don’t want another cell tower built.
“Being an indoor, somewhat controlled environment, DAS solutions typically offer improved user experience by virtue of bringing the (cellular) access closer to users, and with that delivering better signal quality, better data speeds, as well as improved network resource utilization,” said Milan Milanovic, a “technical evangelist” at Ookla, a research firm that runs Speedtest.net, a site where people can check their internet speed.
AT&T is not alone in investing in airport coverage. Since January, Verizon installed antennas in all three terminals and the east and west parking garages. Sprint improved its existing DAS technology at the airport and enhanced outdoor coverage to support the various bands of 4G LTE technology. And T-Mobile tackled the airport train tunnels, Westin Hotel and terminals in an effort that has improved average user success at making calls or accessing internet by 200 percent since last year.
Rich Garwood, T-Mobile’s Regional Vice President for the Northwest, said DAS is just one technology the company has invested in at DIA and throughout the city to improve speed and service. As a result, T-Mobile customers on the DIA network are increasing data use by 110 percent, plus improving call quality and getting fewer dropped calls, Garwood said.
The Denver airport is known for very good Wi-Fi internet service. In July, Ookla ranked the Denver airport as North America’s fastest for free public Wi-Fi. Not only did DIA have the fastest download speed at 78.2 megabits per second, that was a 27 percent increase from the last time Ookla tested airports.
The airport’s cell service also ranked relatively well, with DIA coming in 10th compared to other North American airports, according to Ookla. Average download speeds over cellular connections were 26.3 mbps — an improvement from DIA’s 16 mbps last year.
But outside of the airport, Ookla ranked Denver as one of the worst cities in the nation for mobile download speeds, averaging 12.3 mbps. The city ranked second to last, just behind Portland, Maine, population 66,194.
Analysts have blamed Denver’s poor mobile reception and slower download speeds to factors like increased population, nearby mountains and limited wireless spectrum that each company owns.
The mobile companies say they’re still working on improving service throughout Denver, not just the airport. Verizon said it’s activated about 40 small cells this year “and we’re not done,” said Meagan Dorsch, a Verizon Wireless spokeswoman. “Small cells will help densify our network and add capacity to meet the demand for data today and in the future.”
Sprint has been investing in Denver and appears to be winning because of it. But the company also operates on a different wireless technology than its competitors. RootMetrics, a market research firm that tracks mobile service, named Sprint as Denver’s fastest mobile service earlier this year.
But even with hitting speeds of 19.6 megabits per second, Sprint’s service in Denver was slower than places like Lansing, Mich., where T-Mobile ruled with 50.4 mbps, and Atlanta, where Verizon topped the chart at 41.6 mbps.
“Denver is always going to have challenges specific to the Rocky Mountains,” RootMetrics director Annette Hamilton said at the time. “But I’m telling you that whatever it is the carriers are doing in Denver, it’s making a noticeable difference. There is no reason that any (customers) of the carriers can’t do normal tasks in Denver now, whereas before it was a little hit and miss.”