When it comes to Sprint’s next-generation mobile network strategy, it appears that anything could be in the works. The company has indicated it will reveal its 4G network strategy by the middle of this year. Will it make a flip from WiMAX to LTE? And if so, just how is it going to do it?

In December, Sprint chose Alcatel-Lucent, Ericsson and Samsung to modernize its network — a three- to five-year project that is expected to cost $4 billion to $5 billion. The key to the project is the deployment of new multimode base stations, which Sprint has said will give the operator greater technology flexibility and could allow the carrier to deploy LTE at minimal cost.

Sprint has been wholesaling services from Clearwire’s mobile WiMAX network as its 4G play, but it never gained the first-mover advantage, because Clearwire is hurting for funds and Verizon Wireless has aggressively rolled out LTE services.

Rumors have been circulating. Bloomberg recently wrote that Sprint made a long-term, network-sharing deal with LightSquared, which is planning a wholesale nationwide LTE network in the L-band satellite spectrum. LightSquared hasn’t even launched yet and is embroiled in a battle with the GPS community over whether its operations—regardless where they operate in the band — will interfere with GPS signals (see related story). Sprint isn’t confirming that report, which cited a letter Harbinger Capital senior managing director Philip Falcone reportedly sent to investors of Harbinger Capital partners, which is backing LightSquared.

Still, Sprint isn’t confirming the deal. Clearwire has enough spectrum to deploy LTE alongside its WiMAX operations. It just needs money. Sprint CEO Dan Hesse has indicated this year that Sprint has been in network-sharing talks with Clearwire, too.

In reality, there are multiple options for Sprint. Tim Farrar, principal analyst with TMF Associates, reminded me that last month Sprint noted it could host other spectrum on its Network Vision Platform and specifically mentioned public safety.

Sprint may be waiting to make any sort of announcement until it is clearer that a national public-safety network in the D-block spectrum will emerge. As Farrar pointed it, Sprint would rather have a network-sharing partner that isn’t going to go out of business. While Sprint likely wouldn’t be able to use public-safety spectrum, Farrar said the government could assist in defraying some of Sprint’s Network Vision buildout costs, especially if incentive-based auction money isn’t available for years.

It’s an interesting development that could see a whole host of tie-ups: Clearwire, LightSquared and public safety.

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