The International Telecommunications Union had initially defined "4G" technologies as International Mobile Communications (IMT)-Advanced standards that hit peak theoretical data rates of 100Mbps or higher. Needless to say, none of the current wireless data technologies commercially available anywhere in the world come close to those data rates, and actual IMT-Advanced standards aren't expected to be completed until 2012 at the earliest.
But this doesn't matter much anymore from a marketing point of view, since the ITU threw up its hands late last year and said carriers could use the term 4G to describe any IMT-Advanced forerunner technologies such as LTE, WiMAX and HSPA+. The ITU's reasoning was that such "evolved 3G technologies" provide "a substantial level of improvement in performance and capabilities with respect to the initial third generation systems now deployed." In other words, unless you operate an old-school EDGE network, you can probably get away with calling your network 4G.
So since the term "4G" is used by all major U.S. wireless carriers, and given the fact that it will be a hot topic of conversation at next week's big CTIA Wireless industry event in Orlando, it's a good time to revisit just what kinds of "4G" services carriers are offering and what you can expect from them in terms of data speeds.
-- Verizon became the first major U.S. carrier to adopt LTE (Long Term Evolution) last year and this week is rolling out its first LTE smartphone, the HTC ThunderBolt. LTE is essentially a bridge from 3G technologies such as HSPA and EV-DO Rev. A to the 4G IMT-Advanced technologies that the ITU has in mind. The company made its initial LTE launch in 38 major markets covering roughly one-third of the U.S. population. The carrier plans to have its entire current 3G footprint upgraded to LTE by the end of 2013.
As far as speeds go, initial tests of the LTE network showed data downloads frequently topping 10Mbps in most major markets, although these tests were run when the network just started and didn't have much congestion to deal with. A test released this week by PC World showed that Verizon's LTE laptop air cards provided average download speeds of 6.5Mbps and average upload speeds of 5Mbps.
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