Key figures in the development of 5G assembled last week at the annual Brooklyn 5G Summit in NYC. In two presentations and a panel discussion, attendees heard encouraging updates about the standardization process and its ability to support a global standards-based commercial rollout of the new wireless technology as early as 2019.
Perhaps most significantly, the experts are confident that everything is on track for Release 15 of the 5G New Radio specifications, scheduled for June of this year. Release 15 is critical to the development of 5G because it provides specifications that manufacturers can use to manufacture equipment. For instance, it will describe how 5G base stations will be configured and how those base stations will communicate with smartphones.
The good news is that a decision by the 3rd Generation Partnership Project (3GPP)—a unification of seven telecommunications standards development organizations—to accelerate the 5G New Radio (NR) schedule back in 2017 has not encountered any major setbacks.
Release 15 is so critical to the commercial viability of 5G NR that 3GPP decided early in 2017 to split the release into two phases to ensure its success: the Non-Standalone (NSA) version and the Standalone (SA) version. This phased approach appears to be working.
The NSA version was completed and approved in December 2017, representing the first 5G specification. The NSA 5G NR is based on existing LTE radios and the LTE core network. Also, it really only addresses the radio spectrum below 6 GHz—the spectrum used today for mobile communications that has become a traffic jam.[shortcode ieee-pullquote quote=""We need to look beyond 5G user equipment; it's not just about the handset anymore"" float="right" expand=1]
The first specifications of the SA version of Release 15 will be delivered in June and will be confirmed by September. Peiying Zhu, fellow and senior director, Wireless Technology Lab at Huawei, who is a key figure in the 3GPP specifications, confirmed in her presentation that these specifications will lead to the commerical rollout of equipment that will enable a SA version of 5G NR by the end of 2019.
It will be at this point that 5G mobile networks can begin utilizing the radio spectrum above 6 GHz—a range referred to as millimeter waves—opening up a huge amount of unused radio spectrum. This will make possible new applications for mobile networks, such as Massive Machine Type Communications (mMTC) that could provide low-latency connectivity for robots on a factory floor or vehicles on roads.
Zhu outlined in her presentation some of the key technological features that every new radio on a 5G-enabled base station in the world will be expected to support by the end of 2019. Perhaps chief among these will be the use of massive multiple-input multiple-output (MIMO) antennas and millimeter wave transmission.
The aim in Release 15 for 5G NR is to support natively enhanced MIMO, otherwise known as massive MIMO, according to Zhu. With massive MIMO, the number of antennas moves up from a just dozen or so antennas in today’s MIMO systems to hundreds, thereby multiplying capacity by a factor of 20.
This huge increase in the number of antennas comes with its own set of problems like crossed signals. Technologies such as beamforming, in which signals are targeted directly between a base station and a mobile device, will help sort out those signals.
If one were to try to identify the key feature of 5G, it might be millimeter wave (mmWave) transmssion. The radio spectrum of mmWave resides between 30 and 300 gigahertz, compared to the sub-6 GHz bands used today. While this opens a huge amount of new spectrum, operating at these frequencies means that signals can’t pass through objects in the environment like they can below 6 GHz.
In order to overcome interference problems associated with broadcasting in this part of the radiofrequency spectrum, mmWave transmission will require technologies such as beamforming and small cells, in which a large number of tiny base stations are scattered throughout an environment.
While Zhu’s presenation drilled down into the specifics of the 5G NR specifications, the panel deviated at times to topics like: What will 5G NR do to our handsets? How will machine-to-machine communication or IoT evolve with 5G? Will autonomous vehicles be driven in the cloud?
Arun Ghosh, director of advanced wireless technology for AT&T Labs, said the continued focus on the handset is missing the point of 5G. Ghosh explained that while the fees we pay to use our smartphones represents a stable business, the market for 5G will reside in new applications, such as mMTC. “We need to look beyond 5G user equipment; it’s not just about the handset anymore,” Ghosh added.
Ghosh also addressed mMTC by noting that it may not be fully realized in the first generation of 5G. But he expects some kind of evolution of narrow beam antennas to target a specific area with a signal to enable the Intenet of Things. The specifications of this technology will likely be contained in Release 16 of 5G NR.
While there was some disagreement about how large a role 5G NR will play in autonomous vehicles, Ian Wong, senior manager of National Instruments, pointed out that you don’t really need connectivity to drive a vehicle. “Connectivity provides enhanced safety and infotainment, but the cloud is not driving the car,” Wong added.
Antti Toskala, a wireless standards expert for Nokia, brought the panel back to what to expect as 5G NR continues to move toward its first commercial rollout.
“My expectations are that people will jump on the new spectrum to boost the capacity,” said Toskala. “But then beyond just what the standards say, the devices are more likely to have advanced features. 4G LTE devices have specified these features but they aren’t actually used because there’s less incentive to use them—5G will see a lot of these capabilities delivered.”
Dexter Johnson is a contributing editor at IEEE Spectrum, with a focus on nanotechnology.