While Sprint has been ahead of the game on 4G—despite some product constraints—with their WiMax network, CEO Dan Hesse has seemed surprisingly receptive to jumping to LTE instead. Now we may know why: it’d allow a T-Mobile tie-up.

A possible merger between the two carriers has been rumored for some time, but Hesse’s recent comments to the Financial Times give this puppy some legs:

The network is using an alternative 4G wireless technology called WiMAX, but Mr Hesse said Sprint and Clearwire had sufficient radio spectrum to also deploy an infrastructure involving LTE.

“We have the spectrum resources where we could add LTE if we choose to do that, on top of the WiMAX network,” he added. “The beauty of having a lot of spectrum is we have a lot of flexibility…”

Mr Hesse accepted there was a “logic” to a merger between Sprint and T-Mobile USA if they were both using the same 4G technology, but declined to comment about deal activity.

From a sheer competitiveness standpoint, the deal would be a no-brainer for Sprint and T-Mo, both of whom have recently lagged far behind AT&T and Verizon. The only sticking point really is the network; Sprint would have to either abandon WiMax for LTE or operate both simultaneously, while T-Mobile has thus far stuck with their speedy HSPA+ 3G network instead of committing to a 4G technology.

We’re still a ways off from 4G being pervasive enough that Sprint and T-Mobile could justify a merger based on network commonality. But it’s clear that the right people are at least giving it the right amount of thought. [Financial Times, Image credit: T-Mo News]