T-Mobile may be looking to shake things up again in the cell phone carrier wars.

The company known for its discounts will reportedly unveil a plan Wednesday that offers its prepaid customers unlimited nationwide 4G service for $70 a month.

News of the planned offering was revealed in a promotional graphic leaked to TmoNews, a blog that follows T-Mobile developments.

If accurate, the new plan would replace the current $70 plan, which caps data usage at 5GB a month.

With the merger of T-Mobile with MetroPCS, T-Mobile is expected to become a mighty competitor to Sprint for the prepaid market. Offering unlimited 4G data in a prepaid offering is a sign that T-Mobile is prepared to fulfill those expectations.

The new unlimited 4G data plan is part of T-Mobile's Monthly4G service. That service includes a $50 monthly plan with unlimited talk and text and up to 100MB of data at 4G speeds and a $60 plan with unlimited talk and text and up to 2GB of data at 4G speeds.

T-Mobile offers a number of LTE handsets to prepaid users. They include the Samsung Galaxy Exhibit, LG Optimus L9, theGalaxy S Blaze, and the Galaxy S II.

Although T-Mobile doesn't currently offer an LTE version of Samsung's best-selling Galaxy S III to its prepaid subscribers, it's expected to do so sometime this year, since a version of an LTE version of the S III that appears tailored for T-Mobile was certified by the Bluetooth Special Interest Group last month.

The most notable handset missing in action on T-Mobile's network is Apple's iPhone. That, too, is expected to change this year.

For example, buried in a financial forecast press release last month from T-Mobile's parent, Deutsche Telekom, the company revealed that "T-Mobile USA has entered into an agreement with Apple to bring products to market together in 2013."

Not only will iPhones start appearing in T-Mobile stores but they could start appearing at very reasonable prices. John Legere, CEO of T-Mobile, reportedly brandished an iPhone 4S at Deutsche Telekom's Capital Makets day in Germany last year claiming it could be sold for $99.

If T-Mobile rolls out its unlimited prepaid 4G data plan Wednesday, it will come on the heels of prepaid king Sprint's reported launch of a prepaid service Jan. 25. That service won't support LTE immediately, but that's expected to change later in the year.

Asked why Sprint was launching a branded prepaid service when it already offers prepaid service through Virgin Mobile and Boost Mobile, spokesperson Jayne Wallace explained: "This is essentially a retail initiative for Sprint-branded stores only, created for customers who have an affinity for the Sprint brand and have indicated they wanted a no-contract option. "

She said that selling an in-store prepaid brand would allow the company to strengthen its other prepaid brands by moving resources to promote those brands in its stores to promote them elsewhere.