5G may be the ultimate winner of Project AirGig, the AT&T-led initiative that uses power lines to deliver superfast internet service. Although AT&T doesn’t yet have plans to commercially deploy AirGig, the company is planning on more trials this year that will involve 5G. AT&T is also currently working with vendors and technology partners to build commercial-grade 5G equipment for those trials.
According to Hank Kafka, vice president of access architecture and standards at AT&T, the company isn’t ready to provide details about those vendors or the upcoming trials. However, he did say Project AirGig is making progress, and the operator believes it will be a very complementary technology to 5G.
Kafka said that while AirGig can support a range of different wireless transport technologies including LTE and 5G, he noted that “5G is very high on that list.” Specifically, AirGig could be used to extend 5G millimeter wave (mmWave) signals beyond their current range. AT&T has launched mobile 5G service in 19 markets so far using mmWave spectrum, but using that spectrum has drawbacks because it has a limited range compared to lower spectrum bands.
AirGig technology includes a radio distributed antenna system (RDAS) and mmWave surface wave launcher. The RDAS reconstructs signals for multigigabit mobile and fixed deployments, while the mmWave surface wave launchers can power themselves using inductive power devices without an electrical connection. These devices then create a high-speed signal that travels along or near the wire, providing a broadband connection.
In 2017, AT&T tested AirGig in a trial with Georgia Power Company but used LTE as the transport technology. Kafka said that it used LTE because there wasn’t any 5G equipment available that was appropriate for the trial. “At the time of the trial 5G equipment was large and bulky,” he said. But now 5G is commercially deployed in some markets, and more streamlined gear is available. That’s why AT&T is now working with vendors to get the right type of gear for the new trials.
Nevertheless, the operator believes that early trial with Georgia Power was a success because it showed that the technology was able to transmit a signal regardless of weather or any other issues. And Kafka said that the company also had a good response to its self-install receivers. “Within 10 minutes, customers could get the receiver installed and get access,” he noted.
AirGig for backhaul
Not only could AirGig potentially extend the reach of 5G, but it could also be used as a backhaul technology. “If you set up an architecture where AirGig is connecting to 5G radios, it is acting like backhaul,” Kafka said. “And you can get gigabit speeds and beyond.”
Because AirGig is still in the development phase, Kafka said that AT&T is not currently negotiating any deals with utility companies to deploy the technology on their power lines. However, he did note that AirGig might be a natural technology to support smart grid applications, and that might be appealing to utilities.
He also said that commercialized AirGig would be a good fit for small cells because of the way it is architected. In other words, a wireless signal could travel down the power line and hand off to small cells or be used to backhaul wireless traffic from small cells.
In fact, operators are getting some resistance to the siting of their small cells for 5G, with cities expressing concerns over aesthetics. One solution might be to co-locate small cells with utility infrastructure.