After 2G networks gave way to 3G, 3G networks gave way to 4G, and so you might expect that 5G networks will replace 4G LTE. But that’s not likely to happen, or at least not anytime soon, according to a number of speakers at the
Instead, the speakers I talked to explained that 4G is expected to form the backbone or anchor for networks going well into the future, and will likely continue to be the way most of us get our mobile data, with 5G being used to supplement 4G and provide data for other applications.
“5G is the first G that won’t replace the one before,” said Tod Sizer, who heads mobile radio research for Bell Labs. Sizer said current 4G LTE solutions perform very well for voice, web surfing, and even video, but that new 5G networks will provide more flexibility for applications such as controlling machines on a factory floor, improved reliability compared to Wi-Fi, and better latency than LTE. But he said such networks will likely leverage both 4G and Wi-Fi and add new capabilities on top.
The big difference at this year’s summit, compared to earlier meetings, is that the industry is now “moving from how to what,” Sizer said, as the specifications for 5G get more settled, even though the applications aren’t as clear.
Ken Budka, of Bell Labs Consulting, talked about how 5G will enable “the next industrial revolution,” which will be brought about by combining digital interfaces and sensors on devices and machines with advances in machine learning and AI, all on the future network.
The key to this, Budka said, is the transformative power of low-latency services. Some applications require high bandwidth, and others require low-latency, but most don’t need both with the exception of VR and AR.
Budka noted that in general, 5G will aim to provide one to three milliseconds of latency, compared to about 100 milliseconds in 4G. This is important for a number of applications. For instance, Budka said that in a car moving at 100 kilometers per hour, the difference in latency between 1 ms and 100 ms is half a car length. He also listed other applications, including industrial robotics, 3D printing in construction, cooperative
From a design standpoint, he talked about a traditional core network working fine for 4G and most applications, but that an “edge cloud” would be needed for applications such as VR/AR and system control, where latency is crucial.
5G New Radio
Durga Malladi, Senior VP of Engineering at Qualcomm Technologies, talked about 5G as a “unifying connectivity fabric” serving three broad buckets of applications with very different needs. Enhanced mobile broadband requires enhanced speeds for some applications and the ability to handle more people using more data every year. For a massive Internet of Things network, most of the devices use very little data, but constant low power consumption is key, as these devices need to work for years on small batteries. And you will also have mission-critical services that don’t necessarily use a lot of data but require very low latency.
Malladi talked about continuing to use 4G as a base to provide the core mobile broadband
The key technologies in 5G New Radio include Massive MIMO (which involves using multiple antennas), robust mmWave support, advanced channel coding and DFT-spread, and OFDM-based waveforms for both uploads and downloads. Both stand-alone and non-standalone versions of 5G standards are on track to be approved next year (as part of the 3GPP R15 specification), with the first deployments expected in 2019.
Much of the conversation at the summit was about the 5G New Radio standard, with many discussions about the specifics of many of the technologies, including details on multiple MIMO waveforms.
Mikael Höök, Director of Radio Research for Ericsson Research, talked about how the new radio is necessary for new use cases, including broadband and media everywhere, sensor networks, smart vehicles, control of service, and remote devices. He said standardization is
Höök said the principles behind the design of the new radio include spectrum flexibility, low-latency, a beam-centric design, connectivity, and interworking across spectrum bands.
Many of the technical details Höök described were interesting, particularly as to how the system is designed to enable different use cases. For instance, it includes bandwidth adaptation so it can listen using a narrow bandwidth, but switch to a wide bandwidth when receiving large amounts of data, thus saving power. Other techniques are used to provide low latency and what he called URLLC (“Ultra-reliable and low latency communications”).
In other sessions on the new radio, Huawei Fellow Peiying Zhu gave a talk on
Onoe said the economics of 5G are the “elephant in the room,” as the technology will require the use of many small cells, and will force intense backhaul and backbone modernization, and thus substantial capital expense. But, he said, 5G’s efficiency offers the promise of increased data capacity without increasing capital expense – and in particular cited the use of Massive MIMO and other technologies as opposed to just thinking of the service as a “hotspot service” for complementary use.
Onoe said he is not worried about fragmentation from early versions and said front runners should take responsibility for compatibility. DOCOMO plans a 2020 rollout, he added, which is enough time to set standards.
However, Onoe gave two “dark premonitions.” In wireless technology, the previous generation often booms just before the launch of the next, as happened with enhanced 3G (HSPA+) before the 4G LTE launch. This could happen this time around, he said. Additionally, the industry has historically seen great success only with even-numbered generations, and Onoe wonders if the industry will need to wait for 6G to get everything it wants.
Still, Onoe concluded on a positive note and said that while there are lots of myths about 5G, he believes that the industry should “get on the 5G bandwagon” and create new business models through collaboration across industries.
Progress toward 5G Deployment
Dave Wolter, AVP for Radio Technology and RAN Architecture at AT&T, talked about how the company wants to speed up deployment while still respecting standards, and discussed a variety of tests the company has conducted.
Wolter noted that the December deadline for non-standalone 5G-NR (the standard that uses LTE as an anchor) is crucial because it involves all of the hardware-impacting parts and is necessary so silicon vendors can start designing chips. The idea is to ensure compatibility with the standalone version when that is completed in June 2018. Wolter said AT&T hopes for a standards-based NR deployment of 5G New Radio (NR) as early as December 2018, most likely with fixed wireless first, but with mobility to follow soon after. Still, there remain a number of details left to be decided, he noted.
Wolter described how this would evolve over time, with fixed wireless likely first, then an upgrade to the next generation core, and later to widespread 5G deployment over time. He said AT&T will prioritize a non-standalone mode, and while it has an interest in standalone 5G, that effort will take time. He did note that there is no sub 6GHZ spectrum available for 5G in the U.S. except for around 3.5 GHz, which has other issues. (It is currently used for Defense Department and fixed satellite services, which could theoretically share the spectrum.)
In the meantime, AT&T is most interested in the 39GHz frequency and has done a number of both fixed and mobile tests at 28GHz and 39GHz in partnership with Ericsson and Intel, using techniques such as automatic beam tracking and massive MIMO.
I had the chance to ask Wolter about when he thought we’d see 5G support in handsets, and he said that might have to wait for 3GPP’s Release 16 (as opposed to the Release 15 standards now in development). But he said the big advantage of 5G for mobile broadband is its high density, which provides a better experience when more people are watching video simultaneously, as well as making mobile augmented reality and virtual reality
In a panel discussion, it was clear that different operators across the world have different visions. YongGyoo Lee, SVP for Korea Telecom, talked about having specifications ready so it could offer some 5G services for the 2018 Winter Olympics (though it appears that much of this will be pre-standard technology). Similarly, DOCOMO’s Onoe talked about having a system running for the 2020 Summer Olympics.
However, Frank Seiser, a VP for Technology Innovation at Deutsche Telekom AG, said he saw no driver for standalone 5G as currently proposed, and added that European operators have neither the fixed wireless spectrum the U.S. operators want to use nor the impetus of the Olympics that is driving the Japanese and Korean operators.
In slides presented later at the summit, Seiser pushed the idea of a cloud-native architecture with much more network function virtualization and a service-based architecture but worries that the current Release 15 standards under development don’t provide for these features. Seiser said that a joint industry push for a much more innovative 5G system architecture is needed in order to deliver on the 5G vision. For now, Seiser said, he sees little that you can do better in 5G versus
In the meantime, almost everyone liked the idea of using non-standalone 5G, and all indicated it would be a long time before any of the current LTE
Michael J. Miller is chief information officer at Ziff Brothers Investments, a private investment firm. Miller, who was editor-in-chief of PC Magazine from 1991 to 2005, authors this blog for PCMag.com to share his thoughts on PC-related products. No investment advice is offered in this blog. All duties are disclaimed. Miller works separately for a private investment firm which may at any time invest in companies whose products are discussed in this blog, and no disclosure of securities transactions will be made.