AT&T has added St. Louis, Mo., to its growing 4G LTE network, bringing the carrier's nationwide total to 32 cities.
In addition to St. Louis, AT&T also announced Wednesday that it has expanded its 4G LTE network in Staten Island, N.Y.
AT&T also released a new infographic ( pdf format) about its LTE deployments, listing all 32 cities.
AT&T hasn't stated an average download speed for its 4G LTE network, but said mobile Internet speeds are as much as 10 times faster than 3G service. Testers in markets such as Houston have seen AT&T's 4G LTE speeds in the 7 Mbps to 20 Mbps range, but sometimes in areas where few users were crowding the new network.
AT&T noted that LTE offers lower latency, meaning it will take less time to load a Web page or to see responses in a video call. AT&T began selling the new Nokia Lumia 900 on Sunday for 4G LTE. AT&T also offers the Samsung Galaxy Note and the Pantech Element tablet on the network.
AT&T is considerably behind Verizon Wireless in launching LTE, with Verizon's faster service available in more than 200 cities. Still, AT&T said it is able to reach more than 74 million Americans with 4G LTE.
Among its other claims, AT&T said that when customers are unable to reach 4G LTE, they can revert to AT&T's existing HSPA+ speeds, which are faster than 3G, although AT&T has not specified how fast they are on average.
AT&T said that HSPA+ "enables 4G speeds" but only when HSPA+ is combined with enhanced backhaul, which means that a cell tower has been provisioned with a fiber-optic connection and other infrastructure improvements.
AT&T didn't say how many of its HSPA+ cell towers are backhaul enhanced, although it claim in its infographic that 80% of mobile data traffic runs over enhanced fiber backhaul.
According to figures in the infographic, there have been five wireless speed upgrades at AT&T in recent years, going from UMTS, HSDPA, HUSPA , and HSPA+ to LTE. Those five upgrades were designed to "provide our customers with consistently fast speeds before, during and after LTE deployment," the infographic says. "Other carriers can't say the same."
AT&T's largest competitor, Verizon, has jumped from EV-DO to LTE, without several other upgrades, the infographic notes in a chart.
Matt Hamblen covers mobile and wireless, smartphones and other handhelds, and wireless networking for Computerworld. Follow Matt on Twitter at @matthamblen or subscribe to Matt's RSS feed. His email address is email@example.com.
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