Wireless Week 2012 Leadership Awards:T-Mobile USA didn’t let its meager spectrum resources keep it out of the 4G game.

T-Mobile USA knows perhaps better than most what it is to make do with scarce resources.  

Despite lacking spectrum for LTE, the operator souped up its existing 3G network and boldly marketed the resulting HSPA+ service as 4G. 

The plan began about three years ago under the leadership of Neville Ray, who then served as T-Mobile's senior vice president of engineering and operations. Ray and his team rolled out HSPA+ in Philadelphia in the fall of 2009, expanding it to a number of top East Coast markets, including New York City and Washington, D.C., over the ensuing months.  

In March 2010, T-Mobile announced a major expansion of the HSPA+ service: It would cover not just highly congested urban markets but its entire 3G footprint by the end of that year. 

Within months, T-Mobile had begun telling customers it was offering "4G speeds" on par with those offered by Sprint's WiMAX network. 

“The aggressive pace of our HSPA+ network rollout means our customers can enjoy a better mobile broadband experience on more devices in more places today,” Ray said when T-Mobile began marketing its HSPA+ speeds as 4G. 

After rapidly deploying the service in 2010, T-Mobile announced in March of last year it would step things up a notch with an even faster dual-carrier version of the technology with launches in Las Vegas, New York City and Orlando, Fla.  

Today, T-Mobile says its HSPA+ network covers more than 200 million people, and it's not done expanding the service. Just last month, the operator said it would light it up in eight new markets.

Ray, who has since become T-Mobile’s chief technology officer, illustrated to the U.S. wireless industry that HSPA+ could be a formidable competitor, even as other operators used their more substantial spectrum holdings to move to LTE. \

Phil Marshall, chief research officer at Tolaga Research, says one of the most noteworthy aspects of T-Mobile's HSPA+ push is its work on backhaul, since it could not take advantage of the legacy wireline networks available to competitors Verizon Wireless and AT&T.  

"They had to do a lot more on their backhaul to ensure they could support their bandwidth relatively to Verizon and AT&T, who had significant fixed infrastructure in place," Marshall says.  

T-Mobile has not released specifics on the number of towers which received fiber as part of its move to what it calls “enhanced backhaul,” but says that more than 90 percent of its broadband traffic is currently carried over fiber Ethernet. 

Marshall also gives T-Mobile credit for getting out in front of customer demand, instead of playing catch-up.  

"T-Mobile did well to do that in an environment where they were spectrum constrained and could not move to LTE," he says. "In the U.S. market, if you want to maintain market share you need to be pushing the envelope in terms of bandwidth performance."  

Now that T-Mobile does have the resources to move to LTE, the backhaul it put in place for its HSPA+ service will set a solid foundation for its next generation of wireless service.

"It eliminates backhaul as the immediate bottleneck," Marshall says. 

HSPA+ allowed T-Mobile to use its spectrum more efficiently, allowing them to offer customers higher speeds without additional airwaves. According to 4G Americas, HSPA+ "could match, and possibly exceed" the performance of mobile WiMAX. Since T-Mobile's first foray into the technology, the International Telecommunications Union recognized that certain deployments of HSPA+ could fall under the umbrella of 4G technologies.

T-Mobile laid low for much of last year as it waited out the government's bruising review of AT&T's attempted takeover. The collapse of the deal gave it the spectrum and cash it needed to deploy LTE, and T-Mobile came out swinging earlier this year with its aptly named “reinvigorated challenger strategy” that threw $4 billion at network upgrades and the rollout of LTE. About 37,000 cell sites will get new equipment under the ambitious project.

Even with the additional resources on hand, Ray said in a recent blog post that the company was still eyeing HSPA+84, though its top priority is LTE.  

T-Mobile expects to roll out its LTE network sometime next year. It will still need to be frugal with its airwaves, refarming its 1900 MHz spectrum to open its AWS holdings for LTE, all the while continuing to support its 2G and 3G customers. The new LTE network will run in 20 MHz in three-quarters of its top 25 markets, and the remaining will have to do with 10 MHz. 

There are already signs that Ray plans to be as innovative with LTE as he was with HSPA. The equipment T-Mobile plans to use for its network will be compatible with LTE Release 10, allowing it to capitalize on features of LTE Advanced such as carrier aggregation, which bonds together disparate bands of spectrum into a single, larger channel.  

Given the direction Ray took T-Mobile's HSPA+ network, the possibilities are practically endless for LTE.