Sprint's LTE build out already underway, new 4G network to launch first half 2012?

At this point, it's pretty much an open secret that Sprint needs to hitch its ride to LTE to stay in the wireless game. CNET caught wind of the operator's intended 4G plans ahead of its scheduled October strategy announcement -- an event at which many in the industry expect Sprint to lay out its LTE cards. According to the report, the Hesse-led network's been hard at work installing the necessary infrastructure to convert to its towers to FD-LTE, which is the same flavor of LTE as Verizon and future partner LightSquared. Using the iDEN spectrum it acquired from its Nextel purchase, Sprint reportedly plans to set up 4G shop on those radio waves, and make use of current WiMAX provider Clearwire's proposed switch to TD-LTE by incorporating chipsets in future phones that accommodate both frequencies. The network changeover, rumored to cost Sprint somewhere in the range of $4 - $5 billion, should get carried out over the next five years, laying the groundwork for a true three-way 4G race.