OTTAWA – Telus played host to a vital workshop last week called Tomorrow Is Now: A Workshop on 5G Technology, Operations, and Regulation.
Organized by the International Telecommunications Society (ITS) and featuring a strong roster of international speakers providing the perspectives from all angles including operators, regulators, technologists and academics, the workshop set out the current global 5G marketplace.
The race
Michael Murphy, Nokia’s head of technology for North America, provided a local 5G outlook. He reviewed operator launch plans, noting that soft launches began in the U.S. in 2018. He anticipates that all of the U.S. operators will offer 5G mobile services by the second quarter of 2019. In Canada, we won’t see launches until 2020. Murphy identified the anticipated arrival of the 5G iPhone in late 2020 as being an important milestone for 5G in North America.
He also identified the countries leading in the race to 5G as the U.S., China, Korea and Japan. The workshop featured speakers from three of those countries, with China absent.
During his opening keynote, Clemson University professor Thomas Hazlett joked there is a debate in the U.S. as to whether operators are launching “real” 5G. He views the debate as a good thing, noting that their. market is not being constrained by a regulator on this. He believes the American approach to 5G is a good example of the regulator making spectrum available ahead of market requirements.
(Ed note: The pace of spectrum releases and auctions coming from Industry, Science and Economic Development is something Canadian companies have long complained about.)
According to Murphy, most U.S. operators are launching with existing assets – and the U.S. may be the only country where operators launch 5G using low, mid and high-band spectrum.
4G is the Foundation
Professor Michael Honig of Northwestern University, explained operators are making investments to upgrade and extend their 4G networks in preparation for 5G. According to Honig, these investments are showing significant but modest performance improvement relative to the performance objectives for 5G. Murphy stressed current mobile demand keeps growing and will surpass 4G LTE capacity so operators have no choice but to continue investing in 4G while they build 5G, too.
It’s anticipated 5G will provide much higher data rates than 4G and three-to-four times the spectral efficiency of 4G. Data rates will be greater than 100 Mbps – up to several gigabits per second. In addition to higher data rates, 5G networks will offer ultra-reliable low latency and high connection density to address the demands of the Internet of Things.
Trends for 5G networks include smaller cells, more antennas and more spectrum. We have heard a lot about smaller cells and more sites for 5G, although the speakers at the workshop did not seem to agree on how many new sites will be required. Honig and other speakers explained the importance of millimetre wave frequencies to address the spectrum requirements for 5G. He believes mmwave frequencies are important because there is a lot of spectrum available – about 30 GHz. The frequencies have acceptable attenuation for mobile applications, although he anticipates initial use of the frequencies will be for fixed applications and backhaul.
Gordon Mansfield, AT&T’s vice president of converged access and device technology, explained while much of the 5G foundational work has taken place in various standards bodies, AT&T has made its own strides as it upgrades its 4G network. The company began testing 5G components in a lab environment and then in field trials. It’s also been able to launch very quickly following the publication of 5G standards – perhaps giving fuel to the debate over whether the operators are launching “real 5G”.
Thanks to a partnership with FirstNet, AT&T has been adding antennas to its sites to support the public safety broadband network, and while doing that, it also hung new radios for its own 4G LTE network. The new radios are able to aggregate frequencies which had previously remained disaggregated. This provides the operator with faster broadband speeds, however it’s still not enough to meet customer expectations. These new radios will eventually be upgraded to 5G, through a software upgrade.
Mmwave spectrum is key
Mansfield said AT&T understands it needs to look at mmwave spectrum to address capacity. It began experimenting with fixed applications at its 5G test bed to learn the properties of the spectrum in a live environment.
“mmwave-carried signals were blocked by newer low emissivity (low-e) glass.”
He told the audience AT&T did not experience the expected mmwave signal degradation due to bad weather. As well, signals penetrated materials better than anticipated, but they also encountered new obstacles. For example, double pane glass was not a problem, but mmwave-carried signals were blocked by newer low emissivity (low-e) glass. In urban areas with modern buildings using low-e glass, operators will need to look to in-building antennas to provide coverage.
AT&T’s early retail trial took place in Waco, Texas, where the operator deployed a Wi-Fi system supported by 5G. The system was deployed in a rural location associated with the popular TV series Fixer Upper. The location would periodically swell in population with tens of thousands of visitors. Due to the popularity of the show and its fans, AT&T’s system experienced heavy video upload traffic, but during the trial, wireless speeds of 1.2 Gbps on a 400 MHz channel were achieved, with radio access network (RAN) latency rates at 9-12 milliseconds. The 5G mmwave solution was effectively delivered into a building.
Mansfield noted there have been several reports saying AT&T had launched using 31 GHz spectrum to provide fixed services, but these reports are incorrect. AT&T launched mobile 5G services and plans to leverage 31 GHz spectrum for mobile and fixed applications. According to Mansfield, the high throughput plus low latency makes the totally wireless home or small business quite practical. AT&T launched its services using 31 GHz, however it used 28 GHz spectrum at its test bed. Mansfield believes there will be a device ecosystem to support the use of mmwave spectrum.
Yoji Kishi of KDDI Research, highlighted Japan’s first 5G trial on 4K video transmission over 5G from a drone. The application utilized 28 GHz spectrum.
Dr. Changsoon Choi, of SK Telecom, took the audience through the operator’s evolution to 5G services. SK Telecom commercially launched on December 1, 2018 with a focus on business-to-business services. The operator is utilizing mid-band spectrum, having acquired 100 MHz at 3.5 GHz. SK Telecom has also acquired a whopping 800 MHz of spectrum at 28 GHz.
Choi echoed the comments made by Murphy that access to mmwave spectrum is critical to meeting capacity. He also explained the operator is trying to differentiate 5G in terms of speed, latency, stability and security. Choi said he worries that SK Telecom is not prepared for 5G in the sense of not knowing where customers will want to take 5G.
Network slicing
The operators in Japan and Korea are making use of RAN slicing to virtually separate network resources for a wide variety of services with different requirements. This allows an operator to deliver, for example, low-latency to an autonomous vehicle application for one customer while also providing broadband throughput for a media streaming application to another.
Mid-band spectrum
While Korea has successfully made 3.5 GHz spectrum available, the timing for the availability of the mid-band spectrum in North America is less clear.
Honig explained the U.S. approach to mid-band spectrum. The Citizen’s Broadband Radio Services (CBRS) at 3.5 GHz is 100 MHz of spectrum that is to be shared with the incumbent U.S. Navy (naval radar). A three-tier sharing approach has been developed with the Navy incumbent having licensed access, additional priority licensees having access and then an unlicensed general authorized access level.
He noted the U.S. approach is very complicated, requiring a spectrum database to keep track of spectrum availability information and a system to coordinate and manage shared access to the frequencies.
Hazlett referred to the FCC framework as being very complicated and expensive; also noting the spectrum still has not been made available.
“AT&T has found mmwave spectrum has performed better than expected and the current site density in urban areas should largely address the 5G requirements.”
The FCC’s Matthew Pearl told the audience that CBRS lab testing will be completed very soon and then commercial deployments will be allowed. There are several non-traditional telecom organizations interested in the spectrum, he added. 150 MHz of spectrum will be available at 3.5 GHz. Pearl also indicated that the National Telecommunications and Information Administration is conducting a study regarding the feasibility of using spectrum 3.4 GHz.
Murphy called the Canadian approach to the release of spectrum “logical.” The 600 MHz auction is underway and Minister Bains has indicated that 3500 MHz spectrum could be made available in 2020 followed by high-band spectrum in 2021.
Small sites
Another challenge for 5G is the requirement for additional sites, many more actually. According to Murphy, mmwave spectrum will require two-to-four times the number of today’s sites, however, with mid-band spectrum, operators may be able to re-use the LTE grid of sites. Professor Erik Bohlin of Chalmers University of Technology argued 5G will require a number of cell sites with backhaul on a scale never seen before, suggesting the need for over 700 small cells per square kilometer.
Mansfield acknowledged the need for many more sites, but said the current estimates may be overstated. AT&T has found mmwave spectrum has performed better than expected and the current site density in urban areas should largely address the 5G requirements. This is something Canadian operators have recently been saying, too. In addition to more sites, Choi said that SK Telecom is looking to find a cost-effective backhaul solution when using lampposts as sites.
The workshop concluded with a large panel moderated by CRTC chair Ian Scott. He took the opportunity to ask the panel about access to passive infrastructure, an issue with which the industry is quite concerned. Borrowing from his comments to the Senate Standing Committee on Transport and Communications, he explained that Canada has a complicated jurisdictional model involving the CRTC, ISED, provincial utility regulators and municipalities. Scott worries that the complicated access to passive infrastructure could create obstacles for the deployment of 5G in Canada and he was looking for advice from the panellists.
Pearl explained the FCC action in September 2018 to remove barriers to wireless infrastructure deployment by placing limits on the fees municipalities may charge for processing site applications; and establishing tight timeframes for local authorities to process applications for small sites. Mansfield noted that some municipalities are continuing to challenge the FCC’s decision, so more work must be done. Pearl noted the FCC’s Broadband Deployment Advisory Committee has developed model codes for states and municipalities to help accelerate the deployment of broadband.
Hazlett argued siting in an endemic problem in areas where local authorities have power. Local groups are trying to create monopolies to extract maximum rents and he argued municipalities should instead be looking for orderly ways to deliver competitive services to citizens.
The European regulators are studying best practices. It’s unclear how this will play out in Canada. Hopefully a balance can be struck between municipalities need for revenue and their desires to become Smart Cities.
