Today and for the foreseeable future, Wi-Fi is the technology most devices and applications use to connect to the internet. As technology advances, those devices and applications will require more data to deliver high-quality experiences for increasingly immersive, compute-intensive applications. To further support the emergence of high-fidelity video conferencing, cloud gaming, virtual reality (VR)/augmented reality (AR) and other immersive applications, widespread availability of 10 gigabit and 25 gigabit internet services is just over the horizon.
The real-time nature of these cutting-edge applications will require even faster and higher-performing Wi-Fi, with greater throughput, lower latency and better reliability. Also, because consumers primarily rely on Wi-Fi to connect to the internet — demonstrated by 10 times the amount of data going over Wi-Fi compared with mobile networks and the roughly 80 percent of data from mobile devices going over Wi-Fi — consumers now expect wall-to-wall Wi-Fi coverage in their homes, businesses and wherever they are (e.g., airports, coffee shops, civic centers). More unlicensed spectrum is key to ensuring that Wi-Fi performance keeps pace with consumer expectations and needs.
Identifying and allocating additional unlicensed spectrum for Wi-Fi is critical to ensuring the ready distribution of increasingly capable internet services throughout the home and enterprise. Such efforts will enable the increased performance of today’s and tomorrow’s critical applications in terms of coverage, throughput, latency and reliability, and will support new Wi-Fi features and functionality. In opening the 6 GHz band to Wi-Fi and other unlicensed use in 2020, the FCC took a necessary step toward enhancing the performance and capabilities of Wi-Fi and ensuring the future growth of broadband. However, opening 6 GHz isn’t a one-and-done solution. Additional unlicensed spectrum is needed to enable continued Wi-Fi performance enhancements to stay ahead of both the increasing performance of broadband networks and the growing performance requirements of devices and applications.
Background
Since its inception, Wi-Fi has been designed to use spectrum efficiently and to co-exist with other spectrum users. Wi-Fi uses a contention-based protocol and seeks to transmit data opportunistically in short bursts, when the frequency channel is available, enabling coexistence with other users. Moreover, Wi-Fi devices use a half-duplex access protocol (transmitting and receiving on the same channel) to further economize on available frequency channels.
In 1997, IEEE released the first 802.11 standard, which is the basis for Wi-Fi. From that humble beginning, we’ve seen the adoption of Wi-Fi explode. Today, there are more than 21 billion Wi-Fi devices in use globally. Initially, Wi-Fi used the 2.4 GHz band and provided a data rate of up to 2 Mbps. Over time, Wi-Fi devices began using the 5 GHz band and larger channel sizes to drive increased data rates. With Wi-Fi 6E and the incorporation of channel sizes up to 160 MHz, Wi-Fi devices can support data rates over 1 Gbps.
With the opening of the 6 GHz band (5.925–7.125 GHz), the FCC enabled for the first time 320-MHz Wi-Fi channels. Doing so required the FCC to craft an innovative three-part sharing framework to enable coexistence with the incumbent licensees:
- Low Power Indoor (LPI) requires the use of a contention-based protocol, permits only indoor access points (APs), restricts those APs to a power spectral density limit of 5 dBm/MHz and total power limit of 30 dBm EIRP on a 320-MHz channel, and is available across the entire 6 GHz band.
- Standard Power, enabled by Automated Frequency Coordination (AFC), allows outdoor access points and higher power, up to 36 dBm EIRP (or 23 dBm/MHz on 20 MHz channel), when under the control of an AFC system, and is only available in the UNII-5 (5.925–6.425 GHz) and UNII-7 (6.525–6.875 GHz) portions of the band.
- Very Low Power (VLP) requires the use of a contention-based protocol and enables indoor and outdoor operations at an even lower power limit of -5 dBm/MHz and is only available in the UNII-5 and UNII-7 portions of the band.
The Wi-Fi Alliance officially released Wi-Fi 7 on January 8, 2024. With the available 320 MHz channels in 6 GHz, Wi-Fi can now deliver speeds over 10 Gbps (using four MIMO streams), helping to ensure that Wi-Fi keeps pace with advances in internet service speeds and increasing application requirements.
Driving the Need for Additional Unlicensed Spectrum
U.S. and other governments must continue to allocate additional spectrum for unlicensed use not only to keep pace with the growing demand for Wi-Fi and other unlicensed technologies but also to remain ahead of the technology curve. Allocating additional unlicensed spectrum will fully enable and maximize the benefits of emerging applications and functionality, which will translate to an expected $5 trillion in annual global economic value by 2025. The drivers of necessary additional unlicensed spectrum are discussed below.
Increasingly capable broadband services and growing consumer demand for more connected devices, higher throughput, lower latency and increased reliability. History has made clear that total data usage and bandwidth requirements will only grow in coming years and most of that data will be carried over Wi-Fi, as noted above. This growth will be enabled by the ubiquitous availability of increasingly capable broadband services: 10 gigabit and beyond (e.g., DOCSIS 4.0, 10G-EPON, XGS-PON, 25G-PON). To this end, the U.S. government is investing well over $40 billion to deploy highly capable fiber-based networks. Data and bandwidth usage growth will also be driven by more connected devices and increased use of real-time and data-intensive applications such as new interactive VR/AR experiences. We’ve seen the average number of connected devices per home grow from 13 in 2021 to 17 in Q3 2023 — an increase of over 30 percent in less than two years and a trend we expect to continue. We also continue to see average fixed broadband residential data usage increase — currently, on average, over 640 GB per month. Moreover, the COVID-19 pandemic accelerated the adoption and use of video conferencing and other cloud-based tools. As the FCC has explained, “video conferencing has grown from a niche product to a central pillar of our communications infrastructure.” Because consumers no longer connect devices using an ethernet cable, but rather rely on Wi-Fi to connect to the internet, the government must also continue to make additional unlicensed spectrum available to ensure the government’s investment in broadband deployment actually reaches end-devices and enables the critical applications of today and tomorrow.
Supporting new features and functionality of Wi-Fi 7 and beyond. Additional unlicensed spectrum is also needed to make room for the coming features and functionality of Wi-Fi 7 and beyond. The release of Wi-Fi 7 introduced new features and functionality; of note, Wi-Fi 7 now includes support for 320 MHz channels and Multi-Link Operation (MLO). Both features enable higher throughput and lower latency through the use of wider channels and multiple channels — features not available in prior generations of Wi-Fi. Moreover, IEEE is already working on 802.11bn, the standard that will underpin Wi-Fi 8. The emerging focus is on Ultra High Reliability (UHR) where additional spectrum becomes even more critical to meet performance goals in light of potential channel contention from high-density client environments, adjacent Wi-Fi networks or other unlicensed use.
The technical limitations enabling the 6 GHz innovative sharing framework. The FCC’s innovative unlicensed sharing framework in 6 GHz is a huge success, protecting mission-critical incumbents and allowing for expanded Wi-Fi use at the same time. Moreover, this sharing framework eliminated the need to relocate incumbents, enabling the rapid realization of the benefits of this additional unlicensed spectrum to consumers and enterprise users alike.
To ensure safe coexistence, the FCC established a detailed unlicensed spectrum sharing framework, including Low Power Indoor-only (LPI) restrictions across the band and more recently Very Low Power (VLP) restrictions and database-controlled (by an AFC database) standard-power capabilities available in certain parts of the band, as detailed above. To accommodate these restrictions, Wi-Fi requires more bandwidth to deliver high speeds and employs more spectrum-intensive techniques, such as mesh networking, to achieve the needed coverage. For example, mesh networking requires additional overhead to backhaul and coordinate the mesh traffic, reducing the overall data-carrying capacity of the available channels. One approach to avoid mesh networking is to use a higher-power channel. However, under the current FCC rules, Wi-Fi can access, at most, only one standard-power 320 MHz wide channel through an AFC system.
Between the power limits and other regulatory restrictions placed on LPI and VLP operations and the limited availability of standard power channels under an AFC, the 1,200 MHz available for unlicensed use in the 6 GHz band is unable to provide the needed coverage, throughput, capacity and latency performance that will be expected and required by consumers and enterprise users in the near future. Additional unlicensed spectrum will allow consumers and enterprise users to more fully benefit from Wi-Fi 7’s new features, enabling better user experiences.
It’s Up to Government
Taking all these drivers into account and considering the value that unlicensed spectrum will continue to deliver to global economies, the United States and other governments around the world should waste no time identifying meaningful additional unlicensed spectrum, particularly given that any additional unlicensed spectrum will likely have similar regulatory technical limits as 6 GHz unlicensed use.
