No, this isn't a Zumba routine, but shareholders of wireless service provider Clearwire (Nasdaq: CLWR) are feeling the burn today.

Clearwire last night reported its highly-anticipated fourth quarter results and, continuing with its theme since inception, lost more money that Wall Street had predicted. Although revenue for the quarter rose 107% over the year-ago period to $361.9 million, which was slightly ahead of consensus estimates, one-time writedowns widened Clearwire's quarterly loss to $0.81 – more than double the $0.35 loss analysts had been looking for. So much for that first quarter of EBITDA profits, huh?

The real pound- and profit-buster of last night's routine was the company's fiscal 2012 guidance. Due to the build-out of its 4G LTE network that Clearwire highlighted in August, the company is expecting  revenue to be either flat or slightly down for the year ($1.15 billion to $1.25 billion versus $1.25 billion in fiscal 2011). Capital expenditures are forecast to rise to $450 million, to $550 million.

With extensive losses projected for the immediate future (what's new, right?), we once again need to focus on the only thing of importance to Clearwire investors: its spectrum.

Clearwire holds most of its spectrum in the 2.5 Ghz to 2.7 Ghz range. While not as desirable or as costly as other bands of spectrum, Clearwire still possesses what many feel is a treasure trove of assets. MetroPCS Communications (NYSE: PCS) is actively pursuing additional spectrum, as is AT&T (NYSE: T) additional spectrum being one of the driving forces behind its proposed (but subsequently failed) takeover of T-Mobile from Deutsche Telecom.

What's really sad, though, is that despite offering Clearwire two separate lifelines, Sprint Nextel (NYSE: S) seems hell-bent in not developing its 4G LTE network with the help of Clearwire.

Sprint's original plan was to go with LightSquared, which has, as of yesterday, been told twice now by the FCC to shelve its business plan altogether because it would interfere with certain types of GPS receivers. With LightSquared off the burner, Foolish colleague Anders Bylund noted that Sprint may get desperate enough to cozy up to DISH Network (Nasdaq: DISH) and its own hybrid broadband network. It may not be a match made in heaven, but it's even more evidence that Sprint doesn't want anything to do with its welfare-recipient, Clearwire. 

The Apple iPhone is also playing a crucial role in blocking Sprint and Clearwire from getting together. Even though the iPhone has a net negative effect on margins, all major carriers willingly carry it because of the traffic it eventually drives through their front doors. Unfortunately for Clearwire, the iPhone doesn't work on its network. Clearwire is one of a very select few tech stocks unable to ride the Apple train higher.

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It's really just more of the same for Clearwire: Total cash outflow since 2007 is nearing $8 billion and the company is forecasting more losses for 2012 on increased cap ex spending. At some point here, the company is going to need to show investors it can get customers without the help of Sprint or it's going to need to sell some of its spectrum or risk -- dare I say it yet again -- bankruptcy.

Disagree with my assessment? Tell me in the comments section below and consider adding Clearwire to your free and personalized Watchlist.

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