Radio wave frequencies range anywhere from 3 kilohertz (kHz) up to 300 gigahertz (GHz). Every portion of the spectrum has a range of frequencies, called a band, that go by a specific name.
Some examples of radio spectrum bands include extremely low frequency (ELF), ultra low frequency (ULF), low frequency (LF), medium frequency (MF), ultra high frequency (UHF), and extremely high frequency (EHF).
Spectrum
One part of the radio spectrum has a high frequency range between 30 GHz and 300 GHz (part of the EHF band), and is often called the millimeter band (because its wavelengths range from 1-10 mm). Wavelengths in and around this band are therefore called millimeter waves (mmW). mmWaves are a popular choice for 5G but also has application in areas like radio astronomy, telecommunications, and radar guns.
Another part of the radio spectrum that is being used for 5G, is UHF, which is lower on the spectrum than EHF. The UHF band has a frequency range of 300 MHz to 3 GHz, and is used for everything from TV broadcasting and GPS to Wi-Fi, cordless phones, and Bluetooth.
Likely the most significant difference regarding the next generation of cellular technology known as 5G NR (Fifth Generation New Radio) will be the spectrum. While users will not see this difference, it will manifest for them in the form of higher speeds, lower latency, and a large assortment of new features.
Each spectrum band represents unique properties, meaning there are diverse opportunities for a service provider to balance between throughput, coverage, quality and latency, as well as reliability and spectral efficiency. Availability of spectrum will vary globally between countries and regions, both in terms of bands, amounts and timing.
5G needs a significant amount of new harmonized mobile spectrum so defragmenting and clearing prime bands should be prioritized by governments. Regulators should aim to make available 80-100 MHz of contiguous spectrum per operator in prime 5G mid-bands (i.e. 3.5 GHz) and around 1 GHz per operator in millimetre wave bands (i.e. 26/28 GHz).
5G Bands
5G needs spectrum within three key frequency ranges to deliver widespread coverage and support all use cases. The three ranges are: Sub-1 GHz, 1-6 GHz, and above 6 GHz.
Low-band spectrum is currently being used for 2G, 3G and 4G services for voice, MBB services and Internet of Things (IoT). Newly allocated spectrum for mobile networks include the 600 MHz and 700 MHz bands. These bands are ideal for wide-area and outside-in coverage as well as for deep indoor coverage, typically required for eMBB and voice services.
Sub-1 GHz supports widespread coverage across urban, suburban, and rural areas and help support Internet of Things (IoT) services.
Mid-band spectrum is currently used for 2G, 3G and 4G services. New spectrum has been widely allocated in the 3.5 GHz band, with more spectrum planned to be made available in the 1.5 GHz (L-band) and 5 GHz (unlicensed) bands. Bandwidths of 50 megahertz to 100 megahertz per network will enable high-capacity and low-latency networks ideal for 5G use cases such as enhanced MBB (eMBB) and Ultra Reliable Low Latency Communications (URLLC), for critical IoT applications. With better wide-area and indoor coverage than high-band spectrum, the mid-band spectrum is an optimal compromise between coverage, quality, throughput, capacity and latency. Combining the mid-band spectrum with low-band spectrum leads to exceptional network improvements in terms of capacity and efficiency.
1 to 6 GHz offers a good mixture of coverage and capacity benefits. This includes spectrum within the 3.3-3.8 GHz range which is expected to form the basis of many initial 5G services. It also includes others which may be assigned to, or refarmed by, operators for 5G including 1800 MHz, 2.3 GHz and 2.6 GHz etc. In the long term, more spectrum is needed to maintain 5G quality of service and growing demand, in bands between 3 and 24 GHz.
High-band spectrum clearly provides the anticipated leap in data speed, capacity, quality, and low latency promised by 5G. New spectrum bands are typically in the range 24 GHz to 50 GHz, with contiguous bandwidths of more than 100 megahertz per network. The high-band provides a significant opportunity for very high throughput services for eMBB, localized deployments and low latency use cases, e.g. industrial IoT, venues, etc, both for indoor and outdoor deployments. Fixed wireless access (FWA) will also benefit from these higher bands in terms of capacity. For wider-area coverage, combinations with low-band and mid-band are essential.
Above 6 GHz is needed to meet the ultra-high broadband speeds envisioned for 5G. Currently, the 26 GHz and/or 28 GHz bands have the most international support in this range. A key focus at the ITU World Radiocommunication Conference in 2019 (WRC-19) will be on establishing international agreement on 5G bands above 24 GHz.
WRC-19
WRC-19 will be vital to realize the ultra-high-speed vision for 5G so government backing is essential. The GSMA recommends supporting the 26 GHz, 40 GHz, 50 GHz and 66 GHz bands for mobile – and ensuring that spectrum in bands between 3 GHz and 24 GHz can be secured at the following WRC in 2023.
Exclusively licensed spectrum should remain the core 5G spectrum management approach. Spectrum sharing and unlicensed bands can play a complementary role.
Setting spectrum aside for verticals in priority 5G bands (i.e. 3.5/26/28 GHz) could jeopardize the success of public 5G services and may waste spectrum. Sharing approaches like leasing are better options where verticals require access to spectrum.
Governments and regulators should avoid inflating 5G spectrum prices as this risks limiting network investment and driving up the cost of services. This includes excessive reserve prices or annual fees, limiting spectrum supply (e.g. set-asides), excessive obligations and poor auction design.
Regulators must consult 5G stakeholders to ensure spectrum awards and licensing approaches consider technical and commercial deployment plans.
Governments and regulators need to adopt national spectrum policy measures to encourage long-term heavy investments in 5G networks (e.g. long-term licences, clear renewal process, spectrum roadmap etc).
Canada 5G
“Building a 5G network is like building a home. You need a strong foundation and 600 MHz spectrum is that foundation,” Rogers’ chief technology officer Jorge Fernandes said in a statement, adding it looks forward to combining this spectrum with other “key frequencies including 3500 MHz.”
Regardless of the chosen foundation, it’s clear that Canadian wireless providers will need 3500 MHz spectrum because the frequency range is being established as an international standard, said Gregory Taylor, assistant professor of communication at the University of Calgary.
“Canada can’t go its own way on 5G because of economies of scale,” Taylor said. The band will be critical in cities where thousands of small cells will be deployed, but less helpful in rural areas that require lower bands that can travel greater distances, he said.
While 5G standards are not a done deal yet and many questions remain about 5G’s potential — and whether its benefits will extend to rural areas — Taylor expects intense speculation about the 3500 MHz auction.
“It’s safe to say there’s going to be more interest,” he said. “Bell has kind of been holding its cards the last couple big auctions, which means they’re going to have a big war chest.”
Canada’s government will auction key wireless spectrum for fifth-generation mobile networks in 2020, Innovation Minister Navdeep Bains.
“We believe this puts us in a relatively strong position relative to our international peers,” Bains said prior to his speech at the Canadian Telecom Summit in Toronto.
“We will still be ahead of Australia and Germany and will be (among) the top five countries when it comes to making spectrum available for 5G.”
Industry players — particularly Telus — have called for the auction of 3,500 megahertz spectrum in 2019 to keep up with other countries as smartphone makers bring out devices capable of using 5G networks.
3GPP has three band classes that overlap in the 26 GHz and 28 GHz bands. Band class n257 covers the 26.5-29.5 GHz band, band class n258 covers the 24.25-27.5 GHz band, and band class n261 covers the 27.5-28.35 GHz band. All three band classes support channel bandwidths of 50, 100, 200 and 400 MHz and operate in the TDD duplex mode.
While harmonization with the U.S. continues to be an important factor in establishing Canadian band plans, ISED is of the view that complete alignment with the U.S. for the 28 GHz band is not favourable since it limits access in a given area to two licensees, which could artificially constrain competition in the wireless market. Furthermore, in the mmWave bands, a TDD access scheme will likely be used and coordination between operators will depend heavily on time synchronization of networks, and less on alignment of frequency channels. It is noted as well that using any of the current 3GPP bandwidths of 50, 100, 200 and 400 MHz with the U.S. 28 GHz band plan will result in two 25 MHz blocks potentially being unused.
ISED is of the view that a Canadian band plan based on multiples of 3GPP channel bandwidths would maximize the use of the spectrum, promote a more vibrant marketplace, facilitate international roaming, and enable Canadian consumers and operators to have access to multiple global ecosystems. In addition, a band plan consisting of unpaired blocks of 100 MHz will allow for the flexible use band plan to be aligned with the allocations for the FSS, EESS and SRS, which could reduce complexity when coordinating with these services. Therefore, ISED is adopting a band plan consisting of 18 blocks of 100 MHz with one remaining block of 50 MHz at the upper edge of the band, as shown in the figure below. This band plan will enable the deployment of equipment under 3GPP band classes n257, n258 and n261 in the relevant portions of the 26 GHz and 28 GHz bands.
Recognizing that a multitude of 5G services with differing bandwidth requirements are envisioned, different users may require additional bandwidth to deliver their services. These unpaired blocks may be combined to form larger blocks, subject to the future licensing framework consultation.
References:
Ericsson. (2019). Spectrum Strategies. Telefonaktiebolaget LM Ericsson. Retrieved on October 10, 2019 from, https://www.ericsson.com/en/networks/trending/hot-topics/5g-spectrum-strategies-to-maximize-all-bands
Fisher, T. (2019). 5G Spectrum and Frequencies: Everything You Need to Know.
GSMA. (2019). 5G Spectrum Position: GSMA Public Policy Position. Retrieved on October 10, 2019 from, https://www.gsma.com/spectrum/wp-content/uploads/2019/08/spec_5g_positioning_web_07_19.pdf
ISED. (2019). Decision on Releasing Millimetre Wave Spectrum to Support 5G – SLPB-003-19. Government of Canada. Retrieved on October 10, 2019 from, https://www.ic.gc.ca/eic/site/smt-gst.nsf/eng/sf11510.html
Jackson, E. (2019). Why Canada’s next 5G spectrum auction could be even bigger. National Post. Retrieved on October 10, 2019 from, https://business.financialpost.com/telecom/why-canadas-next-5g-spectrum-auction-could-be-even-bigger
Paddon, D. (2018). Canada to hold key 5G spectrum auction in 2020, says Innovation Minister Bains. CBC.ca. Retrieved on October 10, 2019 from, https://www.cbc.ca/news/business/5g-wireless-spectrum-auction-1.4694214
About the Author:
Michael Martin has more than 35 years of experience in systems design for broadband networks, optical fibre, wireless, and digital communications technologies.
He is a business and technology consultant. Over the past 15 years with IBM, he has worked in the GBS Global Center of Competency for Energy and Utilities and the GTS Global Center of Excellence for Energy and Utilities. He is a founding partner and President of MICAN Communications and before that was President of Comlink Systems Limited and Ensat Broadcast Services, Inc., both divisions of Cygnal Technologies Corporation (CYN: TSX).
Martin currently serves on the Board of Directors for TeraGo Inc (TGO: TSX) and previously served on the Board of Directors for Avante Logixx Inc. (XX: TSX.V).
He has served as a Member, SCC ISO-IEC JTC 1/SC-41 – Internet of Things and related technologies, ISO – International Organization for Standardization, and as a member of the NIST SP 500-325 Fog Computing Conceptual Model, National Institute of Standards and Technology.
He served on the Board of Governors of the University of Ontario Institute of Technology (UOIT) [now OntarioTech University] and on the Board of Advisers of five different Colleges in Ontario. For 16 years he served on the Board of the Society of Motion Picture and Television Engineers (SMPTE), Toronto Section.
He holds three master’s degrees, in business (MBA), communication (MA), and education (MEd). As well, he has three undergraduate diplomas and five certifications in business, computer programming, internetworking, project management, media, photography, and communication technology. He has earned 15 badges in next generation MOOC continuous education in IoT, Cloud, AI and Cognitive systems, Blockchain, Agile, Big Data, Design Thinking, Security, and more.