Sprint begins mobile WiMax network

Sprint Nextel opened its new wireless network to customers in Baltimore on Monday, offering Internet service for laptops for $45 per month. It’s the first commercial network in the U.S. to use so-called WiMax technology for mobile customers.

Compared with more mainstream cellular-broadband technology, WiMax provides fast downloads and is cheap to deploy. Sprint is betting on the technology, championed by Intel, to give it a few years’ head start before cellular broadband catches up.

Sprint’s network carries the “Xohm” brand (pronounced “zoam”) and provides download speeds of 2 to 4 megabits per second, slightly more than twice as fast as the current cellular-broadband networks of Sprint, Verizon Wireless, T-Mobile USA and AT&T.

Sprint is spinning off Xohm into a joint venture with Kirkland-based Clearwire, which already has a WiMax-like network in parts of the country. That deal is expected to close before the end of the year.

Google, Intel and a group of cable companies are investing billions into the venture, which will carry Clearwire’s name.

To use the Xohm network, customers need a $60 laptop card or an $80, coffee-brewer-sized home modem. Sprint expects additional devices, like a USB modem and laptops with built-in WiMax modems, to become available this year.

With the home modem, Sprint will be competing not just with cellular broadband, but with fixed-broadband services like DSL. It will charge $25 per month for home access for the first six months, then $35 per month.

Xohm service will be activated by users online, much the way people sign up for Wi-Fi access at hotels.

In addition to the monthly plans, Sprint will offer a day pass for $10. No contracts are required.

The plan for laptops costs $30 per month for the first six months.

The next cities to get Xohm will be Washington, D.C., and Chicago, according to the Xohm Web site.