"Who has the most 4G coverage?"
That's a deceptively simple question. And the answer to it is an unsatisfying but accurate, "It depends."
It depends on what one means by "4G," by "coverage" and even "most."
The U.S. is one of the fastest-growing 4G markets in the world, thanks to aggressive LTE deployments by Verizon Wireless and AT&T Wireless, and availability of popular LTE smartphones like the recently released Apple iPhone 5 and the Samsung Galaxy S III, not to mention a growing number of tablets.
The carriers are not forthcoming on the number of 4G or LTE subscribers they have. AT&T says "more than 40% of ... post-paid smartphone customers use a 4G capable device." T-Mobile says "nearly 60% of our customers ... carry smartphones, and over half ... are 4G capable." Verizon says nearly "12% of our 89 million retail postpaid connections are 4G LTE as of the 2nd quarter of 2012."
Sprint still offers 4G service based on WiMAX, but in July began deploying LTE. T-Mobile has been expanding its HSPA+21 and +42 network, which is technically considered 4G, and delivers strong performance in several large-scale tests, most recently by RootMetrics' bi-annual "Need for Speed" report.
But investments in LTE are staggering. T-Mobile announced early in 2012 its $4 billion plan to re-equip 37,000 cell sites and refarm radio frequency spectrum to support LTE, focusing first on the top 50 U.S. markets. AT&T announced in November 2012 that it will spend $8 billion "for wireless initiatives" focused on LTE build out over three years. By year-end 2014, AT&T says its LTE service will cover 300 million potential subscribers.
While 4G promises carriers more efficient spectrum use, greater capacity and the benefits of an all-IP network, the benefit for users is data rates that are much faster than 3G. Verizon Wireless and AT&T say LTE subscribers - on a fully loaded network - can expect average downlink speeds of 5M to12Mbps and 2M to 5Mbps on the uplink. By comparison, Verizon's EVDO Rev A 3G network supports average downlink speeds of 600K to 1.4Mbps and 500K to 800Kbps up.
But actual performance can vary widely, as the RootMetrics data also shows. That's because LTE networks are still being built and tuned, and the number of LTE subscribers is still small compared to 3G.
Who has 4G?
Much of the confusion about 4G is due to the fact that multiple radio technologies are labeled 4G by the carriers. Verizon says it has the largest 4G LTE network, while AT&T claims it has the largest 4G network. What's going on?
"The term '4G' has fallen into the hands of the marketing departments," says Roger Entner, founder of telecom consulting firm Recon Analytics. "Everything a carrier now sells you is sold as 4G....They give you '4G LTE' and the 'regular' 4G. That's the hint. LTE is generally the faster."
Technically one can argue that no carrier today offers a true 4G service. That's because the ITU outlined what it considers "next generation" cellular in its IMT-Advanced specification, which is being embodied in two detailed technology specifications, LTE-Advanced and WirelessMAN-Advanced, sometimes called WiMax 2. LTE-Advanced, for example, will deliver up to 1Gbps for a slow-moving mobile user and up to 100Mbps for one zipping along in a car or train, far above existing LTE speeds. (See LTE-Advanced mobile standard gets go-ahead from industry)
Yet neither of these has yet been implemented (though T-Mobile USA says it will begin deploying LTE-Advanced in 2013, its first LTE offering). But with carriers claiming they offer 4G, in December 2010 the ITU issued a release saying "it is recognized that this term ['4G'], while undefined, may also be applied to the forerunners of these [LTE-Advanced and WiMAX 2] technologies, [to] LTE and WiMax, and to other evolved 3G technologies providing a substantial level of improvement in performance and capabilities with respect to the initial third generation systems." [See ITU softens on the definition of 4G mobile]
In practice, this means that anyone using LTE, WiMAX, or HSPA+ today is using "4G." All of these networks deliver far more megabits per second than most existing, older 3G networks. Some of them are doing so by using some of the technologies that will eventually appear in LTE-Advanced and WiMAX2. For the carriers, this is enough to qualify as 4G for marketing purposes.
So who has the most 4G coverage? It depends.
If you're asking about LTE, it's generally accepted that Verizon has by far the largest number of locations with LTE service. On Nov. 15, the carrier announced it has LTE in 440 U.S. markets or cities, faster than originally planned. It expects to complete its initial LTE build out by mid-2013.
A distant No. 2 right now is AT&T, which claims 103. Third of the Big Four is Sprint, which began rolling out LTE in June: it's now in 32 cities.
But these numbers change weekly, sometimes daily. Eighteen months from now, at least in the major markets, there will be little difference in the size of the LTE blankets offered by the Big Four carriers. And there are regional carriers with expanding LTE service: MetroPCS, which was actually the first to go live with LTE, and U.S. Cellular, are examples.
AT&T doesn't claim to have the biggest LTE network, but it does claim to have the biggest "4G" network - a network that includes two cellular technologies: LTE and HSPA+, which now overlays its older nation-wide 3G network. AT&T adds its LTE locations and its HSPA+ locations to say it offers "4G" in 2,000 more locations than Verizon today offers LTE.
T-Mobile doesn't claim to have the biggest 4G network, but it does claim to have the fastest. The carrier has aggressively invested in HSPA+, continually upgrading to faster and faster flavors, most recently the highest performing 42Mbps flavor. And just as aggressively it markets this as 4G.
Tests by PC Magazine, and most recently RootMetrics, show T-Mobile's HSPA+ network often overlaps and sometimes beats Verizon's LTE download performance, though Verizon can far more often top 15Mbps. Via email, T-Mobile says its "nationwide 4G" network is available in 229 markets, reaching well over 220 million potential customers; HSPA+ 42 service is a subset of that coverage: it's in 185 markets, with 184 million potential customers, and growing.
The term "most coverage" is often wrongly understood or interpreted as "best coverage." Either way, it's an irrelevant metric to the vast majority of subscribers. "Ninety percent of the people stay 90% of the time in the same place," Entner says.
For example, on Nov. 12, Verizon Wireless announced it was expanding its LTE network in the Lake of the Ozarks area, a popular vacation spot in central Missouri. One of the lakeside communities around the lake is Osage Beach, with a 2010 Census population of 4,351 people. LTE service may be a godsend to those who live in, or visit, Osage Beach; the news may have been greeted by dancing in the streets. But the vast majority of Americans, and possibly even of Missourians, will never see the town or use Verizon's network there.
For any given wireless subscriber, the question is never "Does Carrier X have 4G coverage in hundreds of U.S. locations?" The question is always "Does Carrier X have 4G where I live and work?" For companies with a field sales or service staff, the question is only somewhat different: they may need coverage in more locations, but they are still specific locations -- they rarely need cellular access from every point in all 50 states.
The meaning of coverage
The word "coverage" can refer to geography, to population, to markets, says Philip Solis, a mobile research director for ABI Research. "They often correlate, but there are different considerations," he says.
Mobile carriers deploying 4G networks first create macro cells that blanket wide areas. Initially, the blanket may not even cover the entire area. Sprint was embarrassed by a recent independent test, whose author Dana Dulabone, founder of consulting firm Advanced Frequency Engineering, concluded that the carrier often had spotty LTE coverage. In a Fierce Wireless follow-up story, Dulabone argued Sprint initially was haphazardly switching on "islands of LTE" in locations like Dallas and Atlanta.
In the most mature LTE markets, however, geographic and population coverage for a given carrier can be over 90%, according to Bill Moore, CEO and president of RootMetrics.
But coverage is only one part of the 4G equation. You also have to take into account network performance and data plans.
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