Most media attention in the cellphone arena is focused on the battle between sexy super-smartphones like Apple’s new iPhone 4 or the latest models based on Google’s Android software. But there is a parallel war under way among U.S. wireless carriers to roll out new, faster data networks to link such sophisticated hand-held computers to the Internet at greater speeds, and to increase the capacity to handle all the data their owners are downloading.
This network competition is less visible and flashy, and it involves complex engineering, long time frames and techie terminology. But it is crucial to the future of these super-smartphones, of tablets like the iPad and its coming competitors, and even of laptops that run on cellular networks when their owners are traveling. The goal is to make wireless Internet access on the street as fast or faster than the access people get in homes and offices, and to overcome capacity limitations.
So, here is a very simplified explanation of what is going on, plus the results of some tests I’ve been running on the least known of these new speedier networks: T-Mobile’s “HSPA+” system, now available in some U.S. metro areas.
In a nutshell, most of the industry is gradually moving from networks dubbed as “3G,” or third generation, to faster networks called “4G,” or fourth generation. This will take several years and billions of dollars, and will be turned on city by city.
In the meantime, two of the U.S. carriers, T-Mobile and AT&T, will be deploying a souped-up interim 3G system, the aforementioned HSPA+ (the faster version of a common system called HSPA, formally known as High Speed Packet Access).
Today, all but one of the fancy super-smartphones that get all the attention, including the iPhone 4, are 3G phones that can’t even take full advantage of the faster HSPA+ variant of 3G. The sole 4G phone in the U.S. today is the Android-based HTC EVO 4G from Sprint, which is the only U.S. carrier already deploying a form of 4G. Sprint’s 4G network is based on a technology called WiMax (for Worldwide Interoperability for Microwave Access) and is now available in 36 metro areas, with more coming.
The two largest U.S. wireless carriers, Verizon and AT&T, are planning 4G networks based on a technology called LTE, or Long Term Evolution. Neither has commercially deployed LTE networks in any metro area yet, though Verizon is pledging to roll it out in up to 30 metro areas by the end of this year. AT&T plans to deploy LTE in an unspecified number of cities starting in 2011, and HSPA+ in an unspecified number of cities starting late this year. T-Mobile, the smallest U.S. carrier, hasn’t unveiled any LTE plans, and is instead doubling down on HSPA+. It has so far rolled out HSPA+ in 25 metro areas, with more coming. T-Mobile claims that although HSPA+ is a 3G technology, it can achieve download speeds akin to 4G networks.
T-Mobile’s new webConnect Rocket
The speeds of all these networks, including the current 3G systems, are fuzzy. The carriers issue marketing claims that often don’t pan out in real use, partly because of variations in location, network congestion and equipment.
In my tests of numerous devices over the years, most 3G phones attained download speeds of between 500 kilobits per second and 4 megabits per second. Laptop data modems generally have done better for me than phones, getting download speeds of between 1 and 5 mbps. Upload speeds on both phones and laptops always have been much slower for me than download speeds.
In May, when I tested Sprint’s 4G EVO phone, running on its 4G network, I averaged download speeds of just 3.4 megabits per second, even though the company claims a “peak” speed of more than 10 mbps and typical real-life speeds of up to 6 mbps. (Peak speeds on all these networks are usually two to three times as high as real-life speeds.)
This week, I tested the new T-Mobile HSPA+ network in two locations in the Virginia suburbs of Washington, D.C., where the carrier told me it had deployed the faster network. T-Mobile has yet to offer a phone that can take full advantage of HSPA+ speeds, though it says 15 of its current phones will go somewhat faster in HSPA+ areas. Its only true HSPA+ device is a laptop data modem called the webConnect Rocket. T-Mobile claims HSPA+ offers peak download speeds of 21 mbps, and says that, in real-life use, its webConnect Rocket should get download speeds of 5 to 8 mbps, and sometimes as high as 10 to 12 mbps.
For my tests, I compared a standard 3G iPhone 4 running on AT&T against T-Mobile’s latest Android phone, the MyTouch 3G Slide. I did a laptop test, comparing the Rocket against a standard 3G data modem from Verizon, called the UM175, using both with the same Lenovo ThinkPad. I disabled Wi-Fi before testing.
In all the tests, the T-Mobile HSPA+ network beat the competition in download speeds, though I never saw the top claimed speeds.
In each spot, I did 10 tests of the devices and averaged their speeds. At the first location, the T-Mobile Slide barely edged out the iPhone, with a download speed averaging 2.84 mbps versus the iPhone’s 2.74 mbps. At the second location, however, the Slide’s edge grew, with an average download speed of 4.26 mbps versus 3.65 mbps for the Apple product.
The laptop tests were much more dramatic. At my first test location, the T-Mobile Rocket drove the ThinkPad to an average download speed of 4.88 megabits per second, versus just 1.36 megabits per second for the Verizon data modem. At the second location, the Rocket achieved an average download speed on the laptop of 6.15 mbps versus 1.58 mbps for Verizon’s modem.
To be fair, the tests were performed in areas of strength for T-Mobile, which may have been weaker coverage areas for AT&T and Verizon. I have gotten much better speeds from the Verizon device in other locations, though never as high as what the Rocket delivered. Also, the Verizon data modem wasn’t the carrier’s newest or possibly its best.
But even though they didn’t back up T-Mobile’s top speed claims, the tests suggest we are heading into a future where the carrier networks may finally catch up with the power of the new smartphones.
Find all of Walter S. Mossber’s columns and videos, free, at walt.allthingsd.com. Email him at mossberg@wsj.com.
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