Searching for Signal in Door County

Editor’s note: Correction appended.

If you have a friend who has visited the peninsula carrying a phone with an AT&T mobile plan, you’ve heard the complaints of spotty service, dropped calls, and a common refrain – “I hate AT&T.”

There’s not a complete blackout, but there are enough gaps in AT&T coverage to make it a struggle to stay connected, especially in northern Door County. This wouldn’t be a problem if it were 1999 and people still vacationed to get unplugged, but with the explosion of smartphone use today, travelers expect to stay connected.

Nielsen market research released a report this spring that showed 37 percent of all mobile phone users now use smartphones, a percentage that is rising rapidly. Many of those smartphone users signed up with AT&T when the wildly popular iPhone was released exclusively through AT&T in 2007.

But why does AT&T, one of the world’s largest telecommunications companies, struggle to provide cell phone and mobile data coverage to Door County, while the much smaller, regional Cellcom can boast substantially better coverage?

I spoke to several people familiar with the county’s wireless infrastructure to get the answer.

The first thing you have to know to understand wireless coverage is that you can’t believe what you see on television, said Tim Ullman, director of Information Systems for the County of Door.

“When you see the national ads on TV for AT&T and Verizon claiming better coverage, the entire country is shown in blue or orange,” Ullman said. “That’s not true. Wireless is line of site and strength of signal.”

Door County’s geography presents a challenge for all companies, even the county’s public safety system. Getting a signal to areas below the bluff requires extra tower sites to bounce signals off.

Wireless providers are licensed by the Federal Communications Commission to transmit on certain frequencies of the public wireless spectrum. When it comes to cell phone service, the lower the frequency, measured in megahertz, the better. Cellcom and U.S. Cellular each own rights to several portions of the 800 megahertz band of the spectrum while AT&T owns rights to portions of the 1700, 1800, and 1900 megahertz bands.

Those higher frequency signals don’t penetrate through foliage like leaves and branches nearly as well as the lower frequencies, which means a provider operating on those bands requires approximately three times the tower sites as a provider operating on the lower bands.

AT&T recently purchased the rights to a 700 megahertz band but is not expected to roll out that infrastructure in Door County anytime soon. The company does not own any of its own towers in Northern Door but partners with Bug Tussel Wireless of Green Bay to provide roaming service. Bug Tussel has similar arrangements in Sauk County, Wisconsin Dells, Dodge County and others, boasting 240 cell sites statewide.

Dolly Guns, sales and marketing coordinator for Bug Tussel, said the company is aware of the “white spots” in coverage in Door County and is working to eliminate them.

“No matter what company you’re with you’re going to have holes, and we know we have some in Door County,” she said.

Jim Greer, an AT&T spokesman, said the company added a tower and capacity in Green Bay this year and service in Door County will improve long term.

“We’ve invested $800 million in infrastructure in Wisconsin since 2008, added eight cell sites, and upgraded 94 sites to mobile broadband capacity,” Greer said. But new towers in Door County aren’t in the company’s immediate plans.

Ullman said that Cellcom, a subsidiary of Nsight Teleservices based in De Pere, has much greater incentive to continually invest in and upgrade its network than national carriers.

“We pride ourselves on having the best coverage in Door County,” said Greg Diltz of Northern Door Communications, a Cellcom partner. “Nobody should say they can cover everybody, but we’re close.”

Ullman said that even though the county could have signed onto the state’s contract with U.S. Cellular for mobile services, he went with Cellcom because it provided the best signal coverage on the peninsula.

“We’re a Northeast Wisconsin company, so we have to serve these people,” Diltz said. “We care about Juddville, Gills Rock, and Washington Island.”

Diltz wouldn’t release proprietary information, but those familiar with the infrastructure said Cellcom has at least 21 tower sites, while Bug Tussel has about two thirds as many.

Verizon reached an agreement with Cellcom in 2009 that enables Verizon customers to roam on Cellcom’s network. AT&T and T-mobile don’t have that option. Those companies operate on the Global System for Mobile communications (GSM) standard, while Cellcom, Verizon, Sprint and U.S. Cellular all operate on Code Division Multiple Access (CDMA) standard, allowing them to partner to provide roaming service. The two standards are not compatible.

Without the possibility of such a partnership, AT&T needs more towers along the peninsula to improve its service. So, until AT&T invests in more towers, AT&T customers visiting Door County will continue to find themselves begging for bars.

Editor’s note: An earlier version of this article mistakenly attributed comments to Diltz that should have been attributed to  another source for the article. The comment “there’s not really a place that Cellcom doesn’t work that somebody else does,” came from a source familiar with the county’s wireless infrastructure, not from Diltz, as did an estimate that Cellcom covers 95 percent of the population and 80 percent of the county’s land area. Both comments came from the same source. The author regrets the error.