Will T-Mobile’s Bet on 3.5G Pay Off?

As the smallest of the four main U.S. wireless operators, T-Mobile often falls below the radar of consumers. Perhaps that’s a desirable situation, because T-Mo is quietly leapfrogging competitors when it comes to mobile broadband speeds. And now there’s talk of the carrier’s first phone coming soon that’s capable to use the full speeds of T-Mobile’s HSPA+ network. Such a phone would signal completion of T-Mobile’s 2010 strategy and position it well for the next steps — a 42 Mbps network upgrade.

A T-Mobile representative shared news of the HSPA+ handset yesterday with Light Reading, saying HTC will build the device for a September delivery. And if a leaked roadmap on AndroidSPIN is to be believed, the HTC Vanguard phone is expected on September 9. T-Mobile responded to our request for comment with an email statement that read: “As announced earlier this year, T-Mobile plans to bring an HSPA+ handset to market in the second half of 2010.  We have not made any further announcements.”

Approximately 15 current T-Mobile phones get faster wireless data speeds through HSPA+, but because their radios top out a 7.2 Mbps, such devices can’t take full advantage of the 21 Mbps HSPA+ network. And even if the HTC Vanguard arrives with full support for 21 Mbps, the T-Mobile overall handset lineup isn’t quite as broad as it’s competitors, who enjoy a wider range of new, higher-end devices. But few of those compete with the speeds that T-Mobile offers with HSPA+.

My own speed testing of the Nexus One in an HSPA+ coverage area topped out around 4 Mbps — much faster than most other phones and networks currently available, but still below what the network is capable of offering. A handset with full 21 Mbps support should see downloads up to 10 Mbps if my hands-on with T-Mobile’s webConnect Rocket is any indication — the device’s radio supports the full 21 Mbps network speed.

As we watch Sprint’s (s s) embrace of WiMAX from 2008 while AT&T (s t) and Verizon (s vz) plan a multi-year march towards LTE, it’s interesting to see T-Mobile’s one-year HSPA+ strategy quickly unfold. (Related: who’s doing what with mobile broadband through 2013.) It was only February of this year that Stacey spoke with Dave Mayo, VP of engineering for T-Mobile, to understand the plans for 2010. Since then, the carrier has blanketed 75 million people with HSPA+ coverage and plans to complete the upgrade before year-end, eventually covering 185 million people.

T-Mobile’s network upgrade is nimble relative to competitors. The carrier has used software upgrades on its cell tower infrastructure to support the faster wireless speeds, while at the same time, transitioning backhaul to 20 Mbps fiber. In June, Chris Hillabrant, a regional VP of engineering and operations for T-Mobile exuded confidence in the strategy, even as competitors struggle to keep up with wireless demand:

Our fiber [backhaul] facilities are highly scalable and we have plenty of wireless spectrum in the big markets, plus efficiencies are gained as we get faster devices on the network. I don’t see any reason we can’t continue to ride the wave ahead of data demand.

Of course, faster wireless speeds increase the data demand wave — once T-Mobile rolled out HSPA+ in New York, the carrier saw a 700 percent increase in demand. That leads to a question of plan pricing and bandwidth caps. For now, T-Mobile offers some of the least expensive plans — I pay $79 per month for unlimited voice, messaging and data — but retains the right to throttle down speeds once a consumer passes 5 GB of data consumption in a month. With AT&T adopting usage-based plans, and Verizon expecting to do the same, will T-Mobile have to follow suit?

It’s unlikely the carrier can stay ahead of the data demand wave forever, so at some point, it’s likely that tiered pricing will arrive for T-Mobile customers. Cole Brodman, T-Mobile’s CTO, couldn’t provide details of such pricing when speaking to Stacey back in March, but hinted at a number of possible scenarios:

I don’t have an answer for you today on what usage-based pricing will look like, whether it’s upgrade buckets, app-based pricing, quality of service-based pricing or time-sensitive throttling.

Brodman may have figure this out sooner rather than later, however. With relatively low data plan rates and a network offering faster speeds than three bigger rivals, consumers in T-Mobile coverage areas could flock to the small carrier. Add an HSPA+ phone or two to the mix and that could speed up the increase in demand before the end of 2010. Such a growth in customers — and the revenues they would bring — sets the stage nicely for T-Mobile to start all over again with a reported 2011 network upgrade to 42 Mbps.

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