Spectrum availability is a fundamental enabler of wireless communications. Nokia is engaged with regulators and industry partners to make harmonized spectrum available for cost-effective 5G deployments while protecting other services.
Access to low, mid and high bands is needed in order to meet the 5G market demands and satisfy different use cases. Low bands such as 600 MHz and 700 MHz provide wide-area coverage and deep indoor penetration for wireless services. Mid bands such as 2.3 GHz, 2.6 GHz, 3.4-4.2 GHz and 6 GHz, provide both coverage and capacity, while the high frequency bands such as 26 GHz, 28 GHz, 40 GHz and 60 GHz offer extreme capacity at specific locations.
Similarly, 5G should make use of licensed, shared and unlicensed spectrum to satisfy the growing data demands. Access to licensed spectrum for exclusive use is the priority to meet the expected demand from 5G networks, but shared and unlicensed spectrum should also be leveraged for the quick and wide adoption of 5G globally.
Here are the key pillars of Nokia’s spectrum policy work.
- Harmonization of spectrum
- National licenses
- Local licensing
- More mid-band spectrum for 5G in the US
- Spectrum for wireless backhaul
Harmonization of spectrum
Globally and regionally harmonized bands are preferred by the wireless industry: larger scale availability of new spectrum bands with clear release timelines creates certainty for the development of wireless technologies, planning of equipment releases and prioritization to achieve economies of scale and reasonable equipment costs.
The World Radiocommunication Conference (WRC) is held every three to four years to review the international treaties governing the use of spectrum. The WRC (WRC-19) held in November 2019 in Sharm El Sheikh, Egypt recognized the significance of 5G growth as a top priority. As a result, a large amount of spectrum totalling 17.25 GHz was identified to further 5G growth. The key WRC-19 decisions include:
- Identifying and globally harmonizing mmWave bands at 26 GHz, 40 GHz and 66 GHz for 5G to drive economies of scale and facilitate roaming that will spur 5G deployments around the world. These mmWave bands will allow ultra-fast 5G use cases such as augmented reality and virtual reality.
- Agreeing on reasonable technical conditions that will govern the 5G use of these bands while protecting other services such as satellite communications. This will positively influence the cost of 5G equipment, ensure that regulators can make the entirety of these bands available and that 5G services can be deployed indoors and outdoors while coexisting with other services.
- Studying mid bands in the 3-11 GHz range for eventual identification for 5G use in four years' time. One such band under study is the upper 6 GHz band covering 6425-7125 MHz, which can become an International Mobile Telecommunications (IMT)/5G band, providing wide area coverage and capacity as well as enabling industrial and other use cases.
- Reviewing of the UHF band (470-960 MHz), which could lead to additional spectrum for 5G in the low bands.
In addition to harmonizing the spectrum bands, aligning the timing for when the bands are available is important to prevent market fragmentation. Deferred access to the spectrum can increase digital divides between countries to the detriment of individuals and businesses and ultimately to the detriment of the overall economy.
In our blog, you can read more about WRC-19 and 3GPP developments supporting 5G growth.
Licensed spectrum provides exclusive rights to use the spectrum without interference and should continue to be the priority for regulators. The duration of spectrum licenses should be long enough (e.g. 10 years or more) to give the wireless industry the necessary timeframe to continuously invest in the latest and most spectrum-efficient infrastructure. Allocation of large contiguous blocks of spectrum should be favored to support wireless broadband.
- Longer license durations and the possibility of extensions offer investors more certainty for continuously investing in state-of-the-art technology. Transparent renewal conditions such as prior notice, timing and conditions of renewal are essential to allow operators to continuously invest in the networks.
- Balanced spectrum pricing policies should permit operators to invest more and faster in networks and services for citizens.
Spectrum is assigned on an exclusive basis in defined geographical regions to operators and/or vertical industries. Local licensing should employ similar regulations to those for national licenses. Aligned regulations enable reasonable pricing and license duration to incentivize local deployments, protection from interference and coordination of licensees if necessary. The regulatory framework should consider the length of the administrative processes and size of the geographical area.
More mid-band spectrum for 5G in the US
While 5G deployments in the US have been focusing on the high (mmWave) and low (600 MHz) bands, other countries have focused on mid-band spectrum, especially between 3.3 and 4.2 GHz. China (3.3-3.6 GHz), South Korea (3.42-3.7 GHz) and Japan (3.6-4.1 GHz) are deploying in these bands while opening additional mid-band spectrum. Similarly, the 3.4-3.8 GHz range is being opened in Europe. This ~3.5 GHz range provides the “sweet spot” for wide area coverage and capacity with better propagation characteristics than mmWave spectrum and larger contiguous spectrum blocks than low bands like 700 MHz. We expect the 3.5 GHz range of bands will support a variety of applications, including enhanced mobile broadband, fixed wireless access and Industry 4.0, with an ecosystem driven by two 3GPP defined bands: n77 (3300-4200 MHz) and n78 (3300-3800 MHz). As such, the 3.5 GHz range is becoming the global roaming band for 5G and needs additional attention in the US. For these reasons, Nokia is a strong, long-time advocate of opening the entire 3.5 GHz range of bands, from 3.3 to 4.2 GHz, for 5G use in the US and elsewhere.
We recognize the fact that the situation in the US is different from other countries in that the 3.5 GHz range is heavily encumbered by federal government and fixed satellite service users. Despite those challenges, the US is taking some actions to address the lack of mid-band spectrum for 5G by opening bands such as the Citizens Broadband Radio Service (CBRS) band covering 3.55-3.7 GHz, C-band (3.7-3.98 GHz) and 3.45-3.55 GHz.
Find out more about the importance of 3.5 GHz spectrum range for 5G in our blog.
Spectrum for wireless backhaul
Microwave links represent one of the most popular solutions to transmit data between base stations and between base stations and network backbones. Microwave links present several advantages such as fast installation and recovery, lower latency and easier access to some base station locations. Recent technology improvements have considerably increased microwave link capacity so that their use is not just limited to areas where fiber optics links are not available. The frequency bands used by microwave links typically extend from 6 GHz to around 100 GHz range and extensions above 100 GHz are being planned.
5G will be the main driver for microwave links in the next few years, needing an extensive use of broadband channels in millimetric bands to provide multi-Gbit/s solutions for backhauling.
We further note that mmWave frequencies used for mobile access are also being considered for wireless backhaul. This technology, called Integrated Access and Backhaul (IAB), shares the same mmWave spectrum at a cell site used by mobile devices to also deliver backhaul connectivity from one cell site to another. By using IAB, operators can provide a faster and cost-efficient method for deploying 5G sites without the need to densifying the fiber transport network to support it. It can also be used to remediate isolated coverage gaps, to enhance capacity, to bridge coverage from outdoor to indoor or to enable group mobility.
Read our blog to find out how IAB can help with 5G mmWave rollout.
Technology neutrality allows spectrum users to move from one technology to another in the same frequency band driven by market demand. This would allow the smooth refarming of spectrum from an earlier generation to a more recent one for a more efficient use of spectrum. Examples include mobile network operators moving from 2G/3G to 4G or even 5G in their spectrum or private mobile radio service users migrating from narrow band to wider band 3rd Generation Partnership Project (3GPP) based technologies in the 400 MHz spectrum to fully benefit from technology evolution.
More fluid spectrum market
A simpler secondary market for spectrum trading would permit operators to optimize their spectrum holdings through trading, leasing and swapping of spectrum. Allocating contiguous blocks of spectrum offers benefits for deploying 5G and should be supported as much as possible.
Managed shared spectrum
Efficient spectrum management should encourage innovative and flexible ways to access spectrum on a shared basis. Spectrum sharing techniques are appealing for 5G systems to access frequency bands used by other services. Examples include:
- evolved Licensed Shared Access (eLSA) in Europe increases the value of the spectrum by opening access to incumbents’ underutilized spectrum to mobile operators or vertical industries. This sharing mechanism enables an efficient use of the spectrum by several services in defined geographies and/or time intervals. eLSA may encourage a more solid secondary market and provide incentives to invest in infrastructure and technology.
- Citizen Broadband Radio Service (CBRS) in the US involves sharing with the incumbent US Department of Defense (DoD) Navy Radar systems and satellite earth stations. These incumbents have priority over all new commercial operations but are only in use in discrete geographic areas and the Navy use is intermittent, allowing for dynamic sharing. Commercial operations are divided into two categories: up to 70 MHz is reserved for Priority Access Licenses (PALs) and at least 80 MHz to General Authorized Access (GAA). All commercial operations (PAL and GAA) are governed by one of several Spectrum Access Systems (SASs), which dynamically manage access to the spectrum. Commercial deployments using the GAA spectrum is already happening and can include the PAL licenses once they are auctioned in July 2020. Nokia is among the companies seeking to be a SAS Administrator with an application currently pending before the Federal Communications Commission (FCC).
Nokia also recognizes the important role that unlicensed spectrum can play in 5G. It is worth noting that in April 2020, the FCC adopted rules that make 1200 MHz of spectrum available for unlicensed use in the 5.925 – 7.125 GHz (6 GHz) band, to be shared with incumbent licensed services. The key historic, incumbent use case in the US 6 GHz band is point-to-point microwave, which is relied on by carriers, utilities, first responders and many others. This fixed wireless use is also important and continues to grow.
To protect these incumbent uses, unlicensed services will be governed by an Automated Frequency Coordinator (AFC), except for low-power indoor operations that the FCC finds will not interfere with incumbent uses. Europe is also studying the 5.925-6.425 GHz range for unlicensed use. The 6.425-7.125 GHz range is being studied for an International Mobile Telecommunications (IMT)/5G identification at the World Radiocommunication Conference in 2023. There is also a possibility for some countries to open part or all of the 6 GHz band for licensed use.
Spectrum for vertical industries
Strategies to effectively encourage vertical industries to adopt wireless solutions should encompass provisions related to:
- Spectrum access, including availability and pricing of spectrum, proportionality of price with the enterprise footprint, and length of administrative processes.
- Collaborative frameworks encouraging cooperation between communications service providers (CSPs) and vertical industries to support the deployment of localized networks given that network deployment requires the specific technical skills and expertise of the CSPs.
Wireless connectivity for vertical industries can be achieved using the following spectrum access models:
- CSP-provided spectrum
Vertical industries can directly access spectrum licensed to CSPs by subleasing or accessing it through direct negotiation with the operator. Examples include subleasing of 3.4-3.8 GHz band in Italy or Finland, local licensing of underutilized bands in the UK, access to Globalstar‘s 2.4 GHz spectrum in the US, and other countries.
- Locally licensed spectrum
With locally licensed spectrum approach, spectrum is assigned on an exclusive basis in defined geographical regions to operators and/or vertical industries. Examples include the 2.6 GHz band in France, 3.7-3.8 GHz band in Germany, 26 GHz in Finland and 28 GHz in Japan.
- Dedicated licensed spectrum
Spectrum identified and reserved at regional/national level for specific applications like public safety and transportation. This includes spectrum reserved for railways, connected cars, public safety and utilities. Examples include 700 MHz for public safety in the US.
- Managed shared spectrum
In the managed shared spectrum approach, “dynamicity” is present, e.g. via dynamic configuration of channel center frequency or bandwidth, maximum permitted power and allowed time for transmission. Channel allocation and operational parameters are controlled by an operational entity (SAS, repository). Examples include CBRS in the US or eLSA in Europe.
- Unlicensed spectrum
The unlicensed spectrum is available for non-exclusive usage, subject to some regulatory constraints, like restrictions in transmission power and without guarantee of interference protection, as in the case of the 5 GHz, 6 GHz and 60 GHz bands in the US and with technology neutral rules that allow various technologies like Wi-Fi, MulteFire and 5G NR-U (unlicensed 5G New Radio).