Sprint to Invest Another $1.5B in Clearwire

In addition to Sprint's new investment in Clearwire's 4G WiMax technology, Clearwire partners Comcast, Intel, Time Warner and Bright House Networks also combine to invest $500 million.

Sprint Nextel plans to invest another $1 billion into Clearwire's WiMax 4G technology with Comcast, Intel, Time Warner and Bright House Networks contributing another combined $500 million, according to the Wall Street Journal.

Clearwire and Sprint Nextel are the only two U.S. carriers betting on WiMax to deliver 4G wireless broadband. Verizon Wireless and AT&T, the nation's two largest carriers, are betting on a rival technology called LTE for their 4G networks. Both WiMax and LTE allow for the delivery of last-mile wireless broadband access, promising faster download speeds than current cellular networks.

Sprint Nextel opened the original U.S. WiMax market in Baltimore last year. Following a merger that saw Sprint turn over its entire 2.5GHz spectrum holdings and its WiMax-related assets, including its Xohm division, to Clearwire,  the newly branded Clear Jan. 6 rolled out a WiMax network in Portland, Ore.

As part of the merger deal, Clearwire also brought in $3.2 billion in WiMax investments from Comcast, Intel, Time Warner Cable, Google and Bright House Networks. Comcast, Intel and Google have already taken write downs on their WiMax investments as Clearwire's stock price has plunged.