AT&T is sharing some of the key findings it discovered in 5G field trials, including that it observed no impacts on 5G millimeter wave signal performance due to rain, snow or other weather events in Kalamazoo, Michigan, and observed a latency rate of 9-12 milliseconds in Waco, Texas.
The operator has been working on 5G for the past couple of years in different parts of the country. “We’re confident we have all the answers we need to deploy a mobile 5G network that works for people all over the country,” blogged Melissa Arnoldi, president of AT&T Technology & Operations.
AT&T reiterated that it will be the first U.S. carrier to launch a standards-based, mobile 5G service and made a point to say that unlike some of its competitors, it plans to offer a 5G-capable device to customers this year. Company executives have said it will offer a mobile “puck” device in time for the launch.
AT&T announced last year that it was expanding its fixed wireless 5G trials to businesses and residential customers in Waco, as well as in Kalamazoo, Michigan, and South Bend, Indiana. In Austin, Texas, it was already seeing speeds up to 1 gigabit per second and latency rates well under 10 milliseconds.
In Waco, it has been working with the home and lifestyle brand Magnolia of “Fixer Upper” fame and reports having provided 5G millimeter wave service to a retail location more than 150 meters away from the cell site. Wireless speeds of about 1.2 Gbps in a 400 MHz channel were observed.
In Kalamazoo, they learned that mmWave signals can penetrate materials such as significant foliage, glass and even walls better than initially anticipated, and observed more than 1 Gbps speeds under line-of-sight conditions up to 900 feet.
In South Bend, they successfully provided gigabit wireless speeds on mmWave spectrum in both line-of-sight and some non-line-of-sight conditions.
Along the way, the research into 5G has sometimes led to new inventions. AT&T actually built its own channel sounder that allows for taking measurements in a matter of milliseconds rather than the 10 or 20 minutes it would take with other channel sounders.
“By conducting these trials and inventing specialized measurement equipment to study other aspects of 5G in great detail, we collected mountains of data and insights to comb through, obsess over and ultimately act on,” Arnoldi said. “These trial learnings are guiding our commercial 5G launches this year and will help ensure we’re building a 5G network that is both real and reliable for everyone.”
Others in the industry have remarked that they were pleasantly surprised to find millimeter wave working better than anticipated, in part due to the way signals bounce off trees and other obstacles.
Nicola Palmer, chief network engineering officer and head of Wireless Networks at Verizon, revealed last fall that Verizon engineers had observed that millimeter wave propagates a little better than expected in terms of line of sight and elevation. For example, they assumed they could get to the 6th floor of an apartment or office building, but their tests showed they were able to get up as high as the 19th floor.
They were also seeing better penetration through various wall materials and latency under 10 milliseconds, which was expected to get lower.