Wireless broadband company Clearwire Corp. said Thursday that founder and cellular pioneer Craig O. McCaw has resigned as board chairman.

    In a regulatory filing, Clearwire said McCaw's Friday departure is not due to any disagreements with the company over its operations, policies, or practices. It didn't comment further.

    Clearwire was formed in 2008 through the merger of McCaw's smaller company of the same name with Sprint Nextel Corp.'s WiMax division. It aimed to create a network that uses WiMax, a new wireless technology that promises faster data speeds than most current cellular broadband networks.

    Sprint is the majority owner, with the rest owned by investors in the original Clearwire, Comcast Corp., Intel Corp., Time Warner Cable Inc., Google Inc. and Bright House Networks. The company operates its network in 68 markets, including New York, Los Angeles, Chicago, Dallas and Philadelphia. It had 2.8 million subscribers by the end of September and predicts it will have 4 million by the end of the year, twice as many as initially expected.

    But Kirkland, Wash.-based Clearwire has been struggling with losses as rising expenses overshadow subscriber growth. The company in November said it would lay off 15 percent of its employees in a move to reduce costs due to a funding shortage.      Earlier this month it completed a $1.33 billion debt offering and said it will use the proceeds for general corporate purposes including capital spending.

    Shareholder Eagle River Holdings LLC said Thursday it will nominate co-founder and former Clearwire CEO Benjamin G. Wolff to fill the seat left vacant by McCaw.

    Shares closed earlier up 8 cents at $5.22.

                                                                                                Source BloomBerg BusineeWeek