As much as we hear about LTE service these days, the fact is that three-quarters of U.S. wireless subscribers still use good old 3G service. For AT&T and T-Mobile, that means HSPA service (although the companies call it "4G"), while for Sprint and Verizon that means CDMA service.
In recent years, all of the major wireless carriers have faced a significant challenge in funding the build-out of their new LTE networks while reserving enough to pay for the upkeep of their existing 3G networks. Such maintenance is important for keeping 3G smartphone users connected to the Web, of course, but it's also critical because all of the carriers still run their voice services over their legacy 3G networks. The migration of voice services to the LTE networks is still years away; when that happens, voice will become an all-IP service (VoIP).
Overall, our tests show that HSPA (T-Mobile and AT&T) service is continuing to outpace CDMA service (Verizon and Sprint) in raw network speed.
T-Mobile's HSPA 14.4 service registered scores of as high as 11.54 megabits per second for downloads, but also had scores as low as 0.02 mbps. AT&T's service was a bit more consistent, hitting in the range of 2 mbps to 4 mbps in most of our test cities. Overall, the average speeds for both carriers rose considerably from last year. (See the chart below.)
The speeds of the CDMA data services from Verizon and Sprint each retreated slightly in this year's tests, as the average speeds for Verizon and Sprint 3G both sat well below 1 mbps. Meanwhile, the average scores of the HSPA services in our tests were at least three times faster than that.
The difference in 3G scores can matter a lot, even if you have a 4G phone. That's because the voice service in your phone runs over the 3G network, and because the phone will almost certainly downshift to 3G service when the 4G signal isn't available.
To evaluate the real-world speeds of the 3G networks, we tested them using an iPhone 4S at ten locations in each of 20 cities. They include Ann Arbor (Michigan), Atlanta, Boston, Chicago, Dallas, Denver, Houston, Kansas City (Missouri), Las Vegas, Los Angeles, Miami, New Orleans, New York, Omaha, Phoenix, Philadelphia, San Diego, San Francisco, San Jose (California), Seattle, and Washington, D.C.
We performed hundreds of tests of each major national carrier's 3G service at each testing location, and then averaged the results to derive an average speed for each city. We then averaged the average city speeds to derive a "national" average speed.
Because wireless signal quality depends to a large extent on variables such as network load, distance from the nearest cell tower, weather, and time of day, we can't predict exact performance in a specific area based on our results. However, the results do illustrate the relative performance of wireless service in a given city on a given day.
T-Mobile wins again
Ever since the U.S. government blocked the merger of T-Mobile and AT&T in late 2011, T-Mobile has taken on an "if you can't join them, beat them" attitude. The company is uniquely positioned to make bold moves: It is the smallest of the four major U.S. wireless carriers, and therefore it has less to lose from making audacious moves in the marketplace.
Not only has T-Mobile launched its own LTE network, but it has also consistently improved the performance of its HSPA network. It has installed new top-of-the-tower equipment to increase the signal strength in 57 of its markets across the United States, covering more than 170 million people. Its HSPA 21 and HSPA 42 networks are now available to 228 million people in 229 metro areas.
The speed scores show it. T-Mobile's 3G HSPA network pumped out the fastest download and upload speeds of any of the major national carriers in our tests for the second year in a row. Using our (HSPA 14.4) Apple iPhone 4S test phone, we recorded impressive average download speeds of 4.97 mbps, and average upload speeds of just above 1 mbps.
"In less than a year, T-Mobile has made huge progress on an aggressive $4 billion plan to make our strong 4G [HSPA] network even stronger," says T-Mobile CTO Neville Ray. "We've advanced our network to increase signal strength and improve voice and data coverage, and we've retuned our airwaves to launch 4G HSPA+ services in additional spectrum, 1900 MHz, that's compatible with a broader range of devices, including the iPhone 4S."
We recorded T-Mobile's most impressive speeds in Chicago and in cities on the East Coast. The service averaged download speeds of greater than 10 mbps in Chicago, New York, Philadelphia, and Washington D.C. And yet T-Mobile 3G had decidedly poor average speeds in some cities. In Omaha, for example, the speed was just 0.02 mbps for downloads, and the service failed to break the 2-mbps mark in several western cities.
Upload speeds were nothing special, amounting to less than 1 mbps in half of our testing cities. Average upload speeds also fell year-over-year in the eight cities common to both this year's study and last year's tests.
While it's beginning the construction of its LTE networks, T-Mobile is trying to compete with the larger carriers by pushing up the speeds of its HSPA service to 4G-like levels, and selling its service plan and device bundles at lower prices. T-Mobile appears to be relishing its "insurgent" role in the mobile market, and consumers may benefit.
AT&T speeds up
AT&T, too, appears to be stepping on the gas pedal when it comes to network performance improvement.
Although AT&T doesn't say exactly how much money it has dropped into its HSPA+ networks over the past year, its speed scores suggest that the investment has been sufficient to meet subscribers' quickly growing demand for data service.
AT&T's 3G service clocked a 20-city average speed of almost 3 mbps. For upload speeds, the service averaged just short of 1 mbps.
Download speeds were reasonably consistent across most of our testing cities; the service posted its lowest speeds in Philadelphia (0.87 mbps), and its highest speeds in Chicago (3.80 mbps). So in Philly it might take 80 seconds to download a 4.5MB MP3 file using the AT&T 3G network, while in Chicago it might take only 18 seconds (assuming a standard network efficiency of 50%).
Still, in the eight cities common to our tests this year and last year, AT&T's download speeds improved only marginally (see the bar chart above), while its average upload speeds remained almost exactly the same. Between our 2011 and 2012 tests, the AT&T 3G service improved considerably; download speeds jumped from 1.63 mbps in 2011 to 2.83 mbps in 2012.
While AT&T is pushing to move as many of its customers as possible onto its new 4G LTE network, it's still maintaining its 3G/HSPA+ service. The company says it will deploy 40,000 small cells and 1000 additional antenna systems nationwide across all networks between now and the end of 2015. That means better quality and coverage--for data as well as for traditional calls and SMS services--in crowded spaces and indoors.
Verizon speeds underwhelm
Verizon does not declare publicly how much it spends on its CDMA network, but its executives say that it intends to maintain the current network's performance until it can move all of its subscribers over to its LTE network.
Verizon 3G averaged .80 (800 kbps) for downloads and .52 (520 kbps) for uploads, on average, in our 20 test cities. Average download speeds broke the 1-mbps threshold only in Dallas, Denver, Kansas City, Philadelphia, San Diego, and San Jose. The service clocked its lowest average downloads in San Francisco, coming in at a sluggish 300 kilobits per second. Downloading an MP3 at that rate would take almost 4 minutes. Verizon 3G upload speeds clustered around the 500-kbps mark for the majority of our test cities.
Verizon's 3G also appears to have gotten somewhat slower over the past year. Download speeds broke the one-megabit-per-second mark (1.05 mbps) in last year's study, when we tested using the HTC Droid Incredible. But when we tested the network in the same cities this year the network averaged only 0.72 mbps. Average upload speeds also moved down slightly in those cities, from roughly 0.73 mbps last year to 0.54 mbps this year.
Still, the scores we recorded this year were within the range of what Verizon tells its 3G customers to expect--download speeds of between 0.60 mbps and 1.40 mbps, and upload speeds of 0.50 to 0.80 mbps.
Verizon's 3G CDMA network covers a huge area of the United States, and now provides the data service for about 70% of the carrier's subscribers. Verizon says it continues to add cell towers to boost signal strength and keep rural areas connected, especially in regions where 4G LTE is not yet available.
Verizon argues that the reliability and reach of the service is really what matters. "For us the most important thing is accessibility," says Mike Haberman, Verizon VP of network operations. "Our philosophy is to get everybody on the network; it's not necessarily all about speed."
Verizon claims that it's seeing more and more of its customer base switching to smartphones as their contracts expire: 61% of Verizon's customers currently have smartphones with data plans. Of those, however, the majority are 3G CDMA phones; only 40%, Verizon says, are LTE-capable.
Verizon executives have talked about phasing out the company's 3G service within the next decade. But actual voice calls are still dependent on CDMA, so Verizon first needs to introduce voice over LTE before we'll see that phase-out begin. According to CFO Fran Shammo, the company plans to launch its first 4G-only devices as soon as voice over LTE becomes a reality.
Sprint 3G still suffering
The other CDMA 3G network in our study, Sprint's network, fared somewhat worse over the past year, despite the carrier's well-publicized "Network Vision" improvement plan. The throughput speeds of the Sprint 3G network declined considerably between our 2011 and 2012 tests, and retreated still more in this year's tests. In our tests this year, Sprint 3G showed dismal average download speeds of roughly 400 kbps (0.40 mbps), and upload speeds of 310 kbps (0.31 mbps).
"We realize customers may experience slower speeds until upgrades are completed in their neighborhoods, as we are simultaneously operating the old and building the new 3G network," says Sprint spokesperson Kelly Schlageter. "In some markets, such as Atlanta and Dallas, the 4G LTE deployment is nearly complete, while 3G work has just begun."
Sprint 3G's worst showings came in Atlanta (200-kbps downloads) and Dallas (300-kbps downloads). The service did not hit average download speeds of greater than 1 mbps in any of the cities we tested. Upload speeds were no better, reaching the 500-kbps mark in only one city, San Francisco.
The company claims that 80% of its customers have 3G/CDMA devices. As part of Network Vision, Sprint is souping up the CDMA network equipment at its sites to increase signal strength, which will result in better data speeds and coverage for 3G devices, the company says.
Sprint says the upgrade will also improve voice service, which runs over the CDMA network. Sprint notes that it began running its CDMA voice service on a new spectrum band (800MHz) in the first quarter of 2013, which it believes will improve in-building coverage and reduce dropped and blocked calls.
Despite our test results, Sprint says that the network overhaul is already having positive effects on its 3G service. In Chicago, for example, where the overhaul is nearly complete, Sprint says that its 3G sites are handling about 30% more traffic on average, and that download speeds have increased by about 15% for sites with upgraded backhaul.
Tune in tomorrow
Tomorrow on TechHive, we'll give you the results of our 20-city study on the speed of 4G networks in the United States. We'll also have a new infographic with a bevy of details on the amazing new LTE networks everyone's talking about.
We'd love to hear about your own experiences with 3G networks. Are the speeds we recorded in your area about what you experience day to day? Let us know in the comments!
This story, "T-Mobile wins 3G shootout, Sprint and Verizon speeds fade" was originally published by TechHive.