US number two operator AT&T launched LTE services in five cities at the weekend, with early network testing from Signals Research Group highlighting strong performance.
As expected, the carrier went live with LTE technology in Dallas-Fort Worth, San Antonio, Houston, Atlanta, and Chicago. By the end of 2011, it promises to reach at least 70 million Americans in 15 major metropolitan areas. It is charging US$50 per month for 5GB of data, similar to competitors such as Verizon Wireless. The data deal also comes with a US$10 per GB overage fee. Its plans require US$3.8 billion in investment, upgrading 44,000 nodes to LTE over a three year period.
AT&T trails Verizon Wireless in launching LTE; the country’s largest operator
last week announced the addition of 26 additional cities and the expansion of networks in Cleveland, Indianapolis and San Francisco, bringing the total number of cities covered by its LTE network to 143, covering 160 million people. However, AT&T’s new network has had positive early reviews. Signals Research tested the network in the greater Houston area, transferring almost 90GB of data over a three-day period using a Sierra Wireless USBConnect Momentum 4G dongle and achieved average downlink data rates of 23.6Mb/s, with peak data rates of 61.1 Mb/s. “Both results meaningfully exceeded our expectations,” noted the firm. The data rate also exceeded 40Mb/s for 8.6 percent of the time and 21Mb/s – the theoretical peak data rate of the operator's HSPA+ network – for 38.2 percent of the time. “Most importantly, the data rate was greater than 5Mb/s for 95 percent of the time,” said Signals Research.
On the uplink, the average throughput was 15.2Mb/s with a peak data rate of 23.6Mb/s. “The uplink results were also much higher than we anticipated,” said Signals. “Sixty percent of the time the uplink Physical Layer data rate exceeded 15Mb/s and 98.2 percent of the time it exceeded 5Mb/s."
Average latency was higher (worse) than the analyst firm expected, coming in at 49ms with a minimum value of 40ms. “That being said, the latency was on par with other LTE networks in the North American market,” noted the report. Handovers from LTE to HSPA+ were declared to be “relatively seamless for a typical data application, requiring 2.4 seconds to exit the LTE network and establish a dedicated connection on the [slower] HSPA+ network.”
Of course, these results are likely to be more impressive than what consumers can expect to receive once AT&T’s LTE networks are in full use. Interestingly, AT&T has shied away from publicly stating specific speeds users can expect from its LTE network upgrade, instead only claiming that “overall, 4G LTE technology is expected to deliver faster peak speeds, and the combination of both 4G HSPA+ with enhanced backhaul and LTE is expected to provide higher speed averages than seen in the past with older versions of wireless technology.” It adds that “many variables affect network speed including spectrum, location, time of day, and other network, device and environmental factors.”
Rival Verizon Wireless has been more vocal in its marketing of LTE speeds. The operator claims average downlink data speeds across the loaded commercial network of 5-12 Mb/s, and 2-5 Mb/s in the uplink.