A Sprint smart phone new incentives with wireless strategy.

A Sprint smart phone new incentives with wireless strategy.

Sprint Nextel Corp. strengthened its hand by being first in the emerging 4G wireless market. It is now poised to become the first carrier to change its 4G strategy.

Millions of Sprint customers already carry devices — such as Evo and Epic cell phones — that run at “fourth-generation” speeds on the WiMax network built and operated by Clearwire Corp.

But Clearwire’s financial strain has brought WiMax’s expansion to a near halt and well short of complete coverage.

Meanwhile, Verizon and AT&T are closing ground on Sprint, pressing ahead with their own networks using a different 4G technology called Long Term Evolution, or LTE.

Even Clearwire has said it might turn to LTE once it garners funding to expand again.

Little wonder that Sprint executives are preparing a 4G strategy announcement sometime before midyear.

They need time because Sprint has many more options than it had a couple of years ago when the company threw in with Clearwire and WiMax.

“It’s really wide open,” said Jonathan Atkin of RBC Capital Markets. “A lot of investors are anxious to hear about the expansion of 4G coverage.”

Sprint’s choices include pumping more money into Clearwire — already 54 percent owned by Sprint — or working out some other way to expand its 4G network’s coverage map.

Sprint may decide to start building its own 4G network — most likely using the LTE technology that is destined to become the dominant form as both of its larger rivals’ LTE networks grow.

And an unconfirmed report last week linked Sprint with a prospective independent LTE network being planned by LightSquared Inc., a potential competitor of Clearwire.