For those of you longing for the go-go days of Project VIP, this may not be it. But in the next five years, AT&T will grow its smalls by up to 90 percent, while macrocells will increase by 10 percent, Krish Prabhu, president, AT&T Labs, and chief technology officer, AT&T, told an audience at the Cohen and Company’s Technology, Media & Telecom Conference, June 2, in New York.
“As we go to enhanced mobile with more bandwidth to the device, small cells will be a key element in the architecture,” he said. “We are looking at it pretty aggressively depending on the market and where small cells make sense.”
AT&T’s spend will shift based on demand, whether it is small cells, new spectrum, new antenna technology, carrier aggregation or sophisticated modulation such as 256 QAM, according to Prabhu.
“The wireless network enhancement never stops, whether it is enhanced mobile broadband or low-latency services for autonomous cars, the wireless network needs to continue to evolve,” he said.
With mobile 5G still many years away, the majority of pre-standard 5G deployments will be in fixed-wireless, according to Prabhu. Besides, he noted the 28 GHz band is only currently allowed by the FCC for fixed wireless use today. AT&T currently serves rural areas with fixed LTE wireless and does not own any 28 GHz, 38 GHz and 39 GHz spectrum but will be in the market for it in the future.
Before 5G-type speeds will be introduced — pre-standard, millimeter-wave, fixed-wireless technology must be proven out and the marketplace economics model must make sense.
“Most of what you will see over the next few years will be fixed wireless applications,” he said. “The question is whether market economics will create the demand for the 5G millimeter wave service, which will provide gigabit-type throughput.”
5G fixed wireless has been helped by advances in smart antenna technology, such as massive MIMO and beamforming and beam steering, and smart receivers, according to Prabhu.
“Massive MIMO works very well at higher frequencies, because the wavelengths are so small you can tap into a lot of antenna elements,” he said. “There is the belief some of the early impediments in field propagation can be overcome with smarter receivers that can reconstruct the signal that has been degraded. Time will tell if the technology is there and there is market demand.”
Unlicensed spectrum, carrier aggregation and millimeter wave frequencies will all play well together in small technology, Prabhu said.
“Unlicensed spectrum has power limitations, and millimeter wave propagation gets very bad after several hundred meters, so they both must be close to the user,” he said. “People are talking about using carrier aggregating to combine unlicensed spectrum with licensed spectrum to get more bandwidth.”