11:15 AM -- Inking a Long Term Evolution (LTE) network-sharing deal with Sprint Corp. (NYSE: S) is the only way I can think of that the would-be 4G wholesaler LightSquared can reach its Federal Communications Commission (FCC) -mandated goal of covering a 100 million people by the end of 2012.

LightSquared is doing very early testing on whether its LTE network could cause interference with GPS receivers at a site near Las Vegas. The company says it will continue with technical testing through 2011 and expects customers to launch services on the network in the first half of 2012.

The Harbinger Capital Partners LP -backed venture currently has a US$7 billion infrastructure deal with Nokia Networks . When I spoke to LightSquared in April, Jeff Carlisle, executive vice president for regulatory affairs and public policy at the company, said it was working on zoning and tower agreements but hadn't deployed base stations yet.

Logically, it is unlikely to deploy much of anything before the final GPS report from the FCC, which is due June 15. Even the company itself now says it will continue technical testing through 2011.

Now, step back in time with me for a moment: Sprint and its WiMax partner, Clearwire LLC (Nasdaq: CLWR), first announced plans to deploy that technology for 100 million potential customers in July 2007. The partnership had some hitches to start with, but "new" Clearwire got a $3.2 billion injection in May 2008 from Google (Nasdaq: GOOG). Clearwire launched its first WiMax market up in January 2009. It didn't reach the goal of 100 million covered, however, until November 2010.

So, at the very most, LightSquared has 18 months to do what it took Clearwire more than two years to do. That's assuming there are no regulatory GPS hold-ups to its first-of-a-kind hybrid satellite and LTE network. Which, of course, is another big question mark hanging over the company right now.

Let's not even get into the funding question yet...

The only way I can see this network hitting the 100 million target is if LightSquared ditches NSN and piggy-backs on Sprint's "Network Vision" plans. This involves Sprint deploying multi-modal base stations that can support CDMA, WiMax and possibly LTE. Sprint CEO Dan Hesse is open to the idea of network sharing, as he's made clear several times. So, LightSquared's future seems to me to hang on two issues:

First and foremost, can it clear up the GPS question? If that doesn't happen then it won't need to worry about deploying a network anyway.

If it does get the green light on GPS, however, it seems to me that LightSquared needs Sprint to have a hope of making its targets.

— Dan Jones, Site Editor, Light Reading Mobile