Until today, T-Mobile USA played coy with its marketing around HSPA+, saying it offered 4G speeds but not actually calling it 4G. With Verizon Wireless about to deploy LTE in 38 markets and the Sprint/Clearwire team making more and more noise about their WiMAX deployments, T-Mobile has apparently decided to bite the marketing bullet and is now proclaiming that its upgraded 3G network is 4G.

Except, technically speaking, it’s not, and neither are the respective WiMAX and LTE deployments coming out from Clearwire and Verizon. If you define 4G by the guidelines set out by the International Telecommunications Union (ITU), there’s not a single 4G deployment in the U.S. today.

The technical definition of 4G seems like a moot point given the marketing that’s already been done around network upgrades. If we’re to judge from press releases and advertisements, a carrier’s definition of 4G is very different from the ITU’s technical specifications.

The U.S wireless industry already has defined 4G through marketing and advertising as technology that offers faster speeds than 3G. After all, that’s all that really matters to subscribers. They don’t care if their “4G” service comes from WiMAX, LTE or HSPA+ - all they care about is that it offers a better experience than 3G.
As squeamish as I am about T-Mobile calling HSPA+ a 4G technology when it’s not even on a path toward ITU certification, are they really doing such a bad thing?

If we’re going to use the end-user experience to define what services can be marketed as 4G, I’d say T-Mobile’s HSPA+ seems to pass muster. The company says people using its webConnect Rocket and new myTouch 4G phone are seeing average download speeds approaching 5 Mbps “in some cities” with bursts approaching 12 Mbps.

By comparison, Clearwire says its “4G” network offers average mobile download speeds of 3 to 6 Mbps with bursts over 10 Mbps and Verizon says we can expect 5-12 Mbps on the downlink from its next-generation service when it launches later this year. MetroPCS Communications hasn’t provided details about the speeds offered by its LTE deployments (which are being done in a comparatively narrow spectrum band).

It doesn’t seem fair to let T-Mobile get away with calling its HPSA+ services 4G when other operators are pouring billions of dollars into deploying next-generation networks, but it’s not like Verizon, Clearwire and Sprint are playing by the rules. Their networks are nearly as far away from 4G as T-Mobile’s, even if the technologies they’re using will some day fit into the ITU’s definition of 4G (with the necessary upgrades).

4G has become more of a marketing term than a technical term, and by those standards T-Mobile is well within its rights to call its HSPA+ network 4G, since it lays claims to speeds comparable to current WiMAX and LTE deployments.

Still, I’m left wondering what T-Mobile will call LTE, when and if they ever roll it out. Since they’re already using 4G to describe their HSPA+ network, what’s left for LTE? Will they dare to call it 5G?