Sprint Nextel Corp announced plans on Wednesday for the first device that would work on both the high-speed WiMax network Clearwire Corp is building and on Sprint's existing mobile network.

Sprint Nextel Corp announced plans on Wednesday for the first device that would work on both the high-speed WiMax network Clearwire Corp is building and on Sprint's existing mobile network.

Sprint, a 51 percent owner of Clearwire, said it would sell the dual-mode modem starting December 21 for $149.99 after a $50 rebate for customers who sign a two-year contract. It is selling Sprint-brand services using Clearwire's WiMax network.

But since the WiMax service has operated only in Baltimore so far, Sprint WiMax customers would have needed a separate device to travel outside the city and use Sprint's own network, which is based on EV-DO technology.

Clearwire is expected to expand the network around the country and expects to launch the service in Portland, Oregan in early January.

Source:Reuters