Yesterday we exclusively reported that Lightsquared would be ditching Nokia for their LTE network build, instead piggybacking on Sprint's base station overhaul being conducted by Alcatel-Lucent, Ericcson and Samsung. Speaking at the Deutsche Bank Media and Telecom Conference today (audio here), Sprint CEO Dan Hesse reiterated Sprint's dedication to Clearwire and WiMax, despite numerous signs the company is ready to go the LTE route, alone if necessary. "Every option that we're looking at, every one includes WiMAX and Clearwire," Hesse informed attendees, while insisting that neither Clearwire or Sprint have made any decision to migrate to LTE.

That's in sharp contrast from what we're hearing from numerous insiders at both companies. Several sources familiar with Sprint's engineering agenda note that Sprint absolutely will be going LTE, though WiMax service will be run simultaneously initially. Aside from the energy efficiency and cost savings, LTE flexibility is among the top reasons for Sprint's recently announced $5 billion base station retrofit.

Insiders familiar with Clearwire's plans meanwhile tell Broadband Reports Clearwire has also already made the decision to embrace LTE -- and the only question is what specific flavor of LTE and what vendor(s). Next month Clearwire executives will attend a test of three different LTE technologies from various vendors, including TD-LTE and FD-LTE, outside of Scottsdale, Arizona. Meanwhile, several Clearwire sources insist the company has placed a freeze on the installation of any new Mobile WiMax basestations.

While it's clear that all of this signals the inevitable death of Mobile WiMax as a serious player in North America (outside of niche application), what isn't clear is the width and breadth of Sprint and Clearwire's future relationship. That won't be fully apparent until Sprint and Clearwire negotiations are complete. Sprint's future plans could very well include Clearwire, though Sprint has been engaged in a significant number of contingency plans in case Clearwire falters, ranging from their as-yet-unannounced partnership with Lightsquared, to this week's renewed rumors of a potential T-Mobile/Sprint merger. Expect Lightsquared to make some of this official at CTIA later this month.