Clearwire Corp. a Kirkland based company serving wireless data network, which is mostly owned by Sprint Nextel Corp. said on Thursday that the 4th quarter net loss of the company widened by thirty per cent as its cost hiked.

In a recent statement, Clearwire Corp. said that its Chairman Craig McCaw is leaving the company – the decision coming at a time when Clearwire has only few days to go for a deadline on critical financial pronouncement by Sprint Nextel, its leading shareholder.

The commencement of Clearwire’s commercial WiMax service – called ‘Clear’ - in South Florida on Monday marks the first time that the company has set foot in a new market without either opening retail stores or buying local advertising.

It was recently told by the executive that Clearwire was planning to sell its WiMAX enabled phones later this year.

It was noted that Clearwire was around 55% percent owned by Sprint Nextel. Clearwire quarter was ended with 971,000 subscribers on revenue of $106.7 million. Around 72% percent compared to a year ago.

Clearwire and Intel have changed a technology deal, which banned the WiMax service supplier from using any other technology, and Clearwire is already in talks with equipment sellers about how it may take on LTE (Long-Term Evolution) for its network.

On Wednesday, Clearwire Corp. reported a loss in quarterly earnings, as it spent heavy amounts on expansion of its high-speed wireless network, but its revenue was well ahead of the estimates pegged by analysts.

In its Wednesday conference call with investors, Clearwire Corp declared that the company is on target with regard to the June launch of Mobile WiMAX in Atlanta, despite a yet another reshuffling of its management. Earlier, the company had also announced its intention of unifying its three existing systems, as a result of a Clear-Xohm merger this summer.

The slightly slower subscriber growth and a reshuffling of its management team notwithstanding, Clearwire Corp. has posted a marginally narrower year-on-year first quarter loss, largely due to increased sales.

The Clearwire-Sprint Nextel combined operations have brought about the official launch of new Clear WiMax service, which is debuting in Portland, Ore.

Clearwire Corp and Sprint Nextel Corp have announced the completion of their merger for building a next-generation wireless data network - Sprint's mobile WiMax Internet network.