What's 4G really mean?
The last 18 months has been very confusing for consumers when it comes to understanding what 4G really means. Marketing masters at the major wireless operators have been throwing around the term pretty loosely the past several months in an effort to one-up each other. To corporate spin artists, 4G is a term used to describe the latest wireless upgrade to faster speeds. But to the International Telecommunications Union, the standards body that defines network technologies, the term 4G has not actually been defined yet.
Part of the requirements for a network to be considered 4G by the ITU is that it it needs to be IP-based and it needs to use orthogonal frequency-division multiplexing (OFDM). The other main requirement is that it needs to support aggregate mobile data speeds of 100 Mbps.
Technically, none of the carriers today claiming to offer 4G services are really offering 4G services. Clearwire, which is building the network that Sprint Nextel is using, uses a technology called WiMax, and Verizon is using a technology called long term evolution, or LTE. These technologies satisfy some of the ITU's requirements for 4G but not all.
T-Mobile uses an extension of its existing 3G technology called HSPA+, which also doesn't satisfy the technical definition of 4G.
But this doesn't mean that these new networks don't represent a new evolution in wireless technology. They do. Each of these network technologies offers a considerable jump in speed over older-generation 3G technologies and data speeds.
Average 3G services offer between 700Kbps and 1.5Mbps. Sprint's WiMax service, built by Clearwire, offers average download speeds around 6Mbps, the company has said. And Verizon claims that tests indicate it is getting download speeds between 6Mbps and 12Mbps on its pre-commercial LTE network.
Just as WiMax and LTE have improved data rates for Sprint and Verizon customers, HSPA+ offers a significant boost in performance for T-Mobile subscribers too. Average download speeds range between 3Mbps and 7Mbps.
(Actual download speeds of wireless networks vary depending on how heavily loaded the network is. Wireless is a shared medium, so the more users you have, consuming more bandwidth, the less capacity is available to go around.)
So what does this mean to the average consumer? In a nutshell, comparing the technologies purely on download speeds, WiMax (Sprint), LTE (Verizon Wireless) and HSPA+ (T-Mobile) are all comparable.
The real competitive difference for these carriers will likely come down to coverage. Clearwire, which is building the WiMax network Sprint is using, is in over 55 markets today and is adding more each week. Its goal is to reach 120 million potential customers by the end of 2010.
Verizon said earlier this week it plans to be in 38 markets across the country and offer service to 110 million potential customers by the end of 2010. And within three years it will be everywhere its 3G service is available today and it will cover 285 million potential customers.
T-Mobile's HSPA+ network is in 65 metro areas today and is available to 120 million potential customers. And by the end of 2010, the company has said it will be available in 100 markets to more than 200 million potential customers.
To get the full benefit of these improved networks, consumers need to get a device that supports the new network technologies. Sprint currently sells two "3G/4G" WiMax smartphones. T-Mobile will soon offer two devices that support its HSPA+ network, the new G2 and HTC myTouch. Verizon hasn't yet announced "4G" devices, but Verizon COO Lowell McAdam said it would announce several new smartphones at the Consumer Electronics Show in January with products in stores in the first quarter.
But consumers also need to be careful when buying supposed "4G" smartphones. Not every device that has a "4" after its name can take advantage of these new networks. For example, the iPhone 4 does not operate on a new generation of AT&T's network. It is simply the fourth version of the iPhone. It operates over the same 3G network that the iPhone 3G and the iPhone 3GS also use.
