For downtown Minneapolis residents who have been wondering when they could get Wi-Fi service in their high-rise apartments or condominums, the answer is: It's starting now.

But even though high-rise dwellers are being connected to the city's wireless network, the service isn't all wireless and it's not Wi-Fi at all.

Instead, it's a technological workaround that's needed because ground-level Wi-Fi signals usually reach only three floors above ground.

Until now, that had left high-rise building residents out of the wireless network, which now serves most of the city (the remaining dead zones are to be served by year's end.) But Wi-Fi network provider US Internet of Minnetonka said it has begun service to its first downtown high-rise, a 34-story residential building at 110 W. Grant St.

But there's more: Building residents can subscribe to download speeds up to 20 million bits per second -- or more than three times faster than the 6 million bit maximum of regular Wi-Fi service, said Joe Caldwell, US Internet's marketing vice president.

The 20 million bit service costs $50 a month. That's less expensive than Qwest, which charges $105 a month for 20-megabit speed. And it's more bits for the buck than Comcast's price of $53 a month for a slower speed -- 8 megabits with occasional speed bursts to 16 megabits. Comcast also offers 50 megabits for $153 a month.

How did US Internet deliver 20-megabit consumer Wi-Fi service over the airwaves? It didn't, because Wi-Fi won't go that fast yet. Instead, the firm used an 800-megabit point-to-point wireless signal that's different from Wi-Fi, which is broadcast in all directions at slower speeds.

That wireless signal connects to an antenna atop the 110 Grant building, Caldwell said. The signal is redistributed inside the building at slower speeds using the same wired DSL Internet technology Qwest uses. US Internet paid for the project, which was more practical than beaming short-range Wi-Fi signals around the building, Caldwell said.

"Because there are about 300 units in that building, there were enough potential customers that we could afford to build this ourselves," he said. "But we also wanted to experiment with it."

As a result, building residents can connect to the Wi-Fi network at either the 1-, 3- and 6-megabit download speeds offered in other parts of Minneapolis (see prices at www.usiwireless.com/service/pricing.htm) or faster 10-megabit ($40 a month) or 20-megabit speeds.

US Internet hopes to provide service to at least one other downtown high-rise, and perhaps to several, Caldwell said.

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