Expanding Wi-Fi Capacity

Expanding Wi-Fi Capacity

FCC opens up more unlicensed wireless spectrum, enabling the game-changing Wi-Fi 6E standard.

Many people working from home due to the COVID-19 pandemic depend upon Wi-Fi to connect their mobile devices. In densely populated areas, they may be competing with their neighbors for wireless spectrum. That’s because the 2.4GHz frequency band used by most smartphones and tablets has a limited number of channels. Newer devices use the 5GHz frequency band, but that space is becoming crowded as well.

The FCC is addressing this challenge by opening up more of the unlicensed wireless spectrum for Wi-Fi use. On April 23, FCC commissioners voted unanimously to allocate 1200 megahertz of the 6GHz frequency band, paving the way for faster Wi-Fi connections. This will provide about six times as much spectrum as the 2.4GHz and 5GHz bands currently in use and make it possible to create seven 160MHz channels that don’t overlap.

The Wi-Fi Alliance responded by extending the Wi-Fi 6 standard to encompass the 6GHz spectrum, ensuring that Wi-Fi users can benefit from additional capacity, wider channels and less congested spectrum. Manufacturers are moving quickly to introduce compatible products, with initial forecasts expecting more than 316 million Wi-Fi 6E devices to enter the market in 2021.

Significant Expansion

Today’s Wi-Fi networks typically have plenty of coverage, but they often lack the capacity to support growing numbers of mobile devices. The 2.4GHz frequency band has only three 20MHz channels that don’t overlap, so neighboring networks often compete with one another.

The 5GHz band offers more channels and there aren’t as many devices competing for access. However, it doesn’t reach as far as the 2.4GHz frequency band. Additionally, a good chunk of the 5GHz spectrum is regulated to prevent interference with radar. Rather than attempting to navigate that complexity, many manufactures design their devices to avoid the regulated channels.

The 6GHz band (technically 5.925GHz to 7.125 GHz) is currently being used by microwave services that support wireless backhaul, utilities and public safety, but the 1200 megahertz being allocated represents a substantial amount of capacity. The FCC will be crafting rules governing how unlicensed Wi-Fi networks will share spectrum with those licensed services. Those rules will be implemented in Wi-Fi 6E, which isn’t a new protocol but an expansion of the Wi-Fi 6 standard.

A Look at Wi-Fi 6

Wi-Fi 6 (also known as 802.11ax) already offers significantly greater performance and capacity than its predecessors. It has a 160MHz spectrum channel, four times wider than those used by Wi-Fi 5 (802.11ac), and uses a technology called orthogonal frequency division multiple access (ODMFA) to break the channel down into hundreds or even thousands of subchannels. This allows up to 18 clients to send data simultaneously without creating signal contention or congestion.

The Wi-Fi 6 standard also builds upon the multiuser, multiple input, multiple output (MU-MIMO) capabilities introduced with 802.11ac Wave 2 products. While the older single-user MIMO technology supports just one user transmission, MU-MIMO allows up to four simultaneous user transmissions per spatial stream. Wi-Fi 6 takes this even further by supporting eight simultaneous streams and using beamforming technology to accurately aim those streams at the receiver’s antennas.

As a result, Wi-Fi 6 delivers up to 400 percent greater capacity and is more effective in high-density settings such as large lecture halls and public venues. Latency is vastly improved, allowing for near-real-time use cases. Wi-Fi 6 is also easier on connected devices’ batteries and overall provides a more predictable user experience.

New Applications

Still, Wi-Fi remains a shared medium. More users, devices and applications mean more wireless traffic and less bandwidth to share. The FCC’s expansion of the unlicensed spectrum will help ensure that Wi-Fi can support ever-increasing demand.

The 6GHz frequency band addresses Wi-Fi’s spectrum shortage with greater capacity and less interference from legacy Wi-Fi devices, enabling multigigabit Wi-Fi speeds and more devices performing optimally on a Wi-Fi network at once. It capitalizes on the benefits of Wi-Fi 6, paving the way for higher-performance, lower latency devices and networks.

Wi-Fi 6E will provide higher resolution streaming for applications such as video conferencing, lower latency for gaming and industrial IoT, and faster download speeds for critical services in education and healthcare. Users will also see a new generation of mobile devices, including those that deliver bi-directional video and virtual reality (VR) applications.

“We expect initial Wi-Fi 6E products to enter the market this year, with the first Wi-Fi 6E access points available by the fourth quarter of 2020,” said Phil Solis, research director at IDC. “We expect Wi-Fi 6E will gain momentum and see rapid 2021 adoption with more chipsets targeting flagship smartphones, PCs, TVs and even VR devices.”