Cees Links is a Wi-Fi pioneer and the founder and CEO of Greenpeak Technologies and currently General Manager of Qorvo’s Wireless Connectivity business unit.
The Wi-Fi 6 standard runs in the so-called unlicensed, low-power 2.4 GHz and 5 GHz frequency bands. These bands have been in place since the beginning of this century following quite a long process, as each country has the autonomy to assign band usage within its own territory. In the years running up to 2020, the Wi-Fi industry has worked with about 80 MHz in the 2.4 GHz space and 580 MHz in the 5 GHz space – 660 MHz in total.
There are two possibilities to get more data at higher speeds through the air: more bandwidth (more frequency bands) or more sophisticated radio communication (more megabits per MHz). Over the last 20 years and several generations of Wi-Fi, the data rate has increased by using more advanced radio technologies. The original 11 Mb/s of 802.11b was followed by 802.11a, 802.11g, 802.11n, and so on, with the data rate going up into the multi-gigabits per second. At the same time, the calls grew louder for the governments to provide more unlicensed spectrum.
Around 2010, a new frequency band was made available in the 60 GHz space with a lot of spectrum and a lot of bandwidth – almost 13 GHz. The idea was to be able to go to very high data rates – and indeed, Gb/s were achieved. A standard was even developed, called Wi-Gig or IEEE 802.11ad. But the range, about 3 meters, was disappointing. As the number of applications requiring very high speeds over very short distances (‘Bluetooth on steroids’) was limited, the usage of the 60 GHz space hasn’t gotten much commercial traction.
In 2019, there was worldwide momentum to make 6 GHz available as a low-power unlicensed band because several applications using 6 GHz had started to fade away. This coincided with reports showing the economic value of Wi-Fi returning in taxed profits, taking away the concerns about ‘giving away’ spectrum to the industry. Governments prefer to license spectrum, so they can immediately monetize the usage in license fees, while unlicensed spectrum is only indirectly monetized through taxes on economic activity generated through the usage of that spectrum. In the US, there was strong momentum to match the amount of spectrum licensed for 5G with a comparable amount of unlicensed spectrum for low-power, indoor applications, of which Wi-Fi is one of the best known. This led in April 2020 to the FCC announcement to ‘un-license’ the 6 GHz band for low-power usage.
And thus, Wi-Fi 6E was born – the new Wi-Fi standard that extends Wi-Fi 6 into the 6 GHz space. The 1,200 MHz of available bandwidth is a sizable extension compared to the combined 660 MHz that was available previously. Initially, we’ll only see Wi-Fi 6E as an increase in capacity – the number of Wi-Fi connections that can be used at the same time (eg more users in the home using demanding networking applications, including video and gaming). The real next steps in higher data rate, together with exploiting the higher capacity, will be made when Wi-Fi 7 comes into fruition.
Other countries have picked up the challenge. The end of 2020 saw a growing list of locations where Wi-Fi 6E technology can be applied. In Europe, the UK took the lead and via the ETSI, the rest of the continent is expected to follow. (In Europe, at least for now, only the lower part of the 6 GHz space will be made unlicensed – about 500 MHz.) South Korea and several South American countries (Brazil, Chile, Peru) have decided to follow America’s 6E expansion.
Furthermore, the FCC has proposed to add a 45 MHz band to the 5 GHz unlicensed spectrum. With 1,200 MHz available in the 6 GHz space, why is this important? Because the available unlicensed 580 MHz in the 5 GHz spectrum was just falling short of being able to accommodate three simultaneous high-speed 5 GHz channels. The additional 45 MHz solves that problem, allowing the development of more advanced products within the 5 GHz space.
Over the last 20 years, Wi-Fi has accelerated from 11 Mb/s to almost 10 Gb/s – close to a factor of 1000! The 6 GHz addition will pave the way for engineers to figure out whether another factor of 1000 is achievable over the coming two decades.