Wide-open spaces: Big spectrum gains to boost Wi-Fi capability in 2021

Two recent FCC decisions will dramatically increase the capabilities of new Wi-Fi systems in the coming year, providing badly needed breathing room to the unlicensed wireless world.

The first allocation, announced in April, will throw open the entirety of the 6GHz spectrum range for unlicensed use, and the second, rolled out late last month, adds a small but critical amount of spectrum to the 5GHz band.

Both of these decisions are important to future Wi-Fi deployments because they directly affect the amount of spectrum available for Wi-Fi to operate in. More bandwidth means larger channels, which translates directly into improved throughput for users.

6GHz: The new frontier

The April announcement marks the biggest sea-change for Wi-Fi-usable spectrum since the early 2000s, adding a whopping 1200MHz of spectrum to the existing 600MHz currently available to unlicensed users. Where current generations of Wi-Fi technology generally don’t use channels wider than 80Mhz, the 6GHz spectrum opens up the possibility of multiple 160MHz channels—capable of real-world throughput in the gigabit range.

“The fact that we’re getting 1200MHz of new spectrum sets us up for the next 10 years,” said Dave Wright, head of spectrum policy and standards at CommScope, which is the parent company of Ruckus Wireless.

Devices capable of using that spectrum will be branded Wi-Fi 6E, and the industry is moving quickly to provide hardware capable of using it. Broadcom recently received the first FCC certification for a 6GHz-capable chipset, and the consensus is that enterprise-grade access points should start to become available by the end of 2021. Those access points will also have the advantage of not having to cope with older, less-optimized traffic common to the older 2.4GHz and 5GHz bands, according to Bob Friday, CTO and co-founder of Mist Systems, a wireless platform company now owned by Juniper.

“That tends to slow everything else down in the band, so with the 6GHz band we won’t have those slow cars on the highway,” he said.

5.9GHz: An important tweak

The most recent allocation, which gives 45MHz of spectrum to the unlicensed world, is much smaller in scale, but could produce noticeable effects for Wi-Fi technology even sooner. That new spectrum is enough to allow 5GHz Wi-Fi setups to use three separate 80MHz channels, which is a critical consideration for enterprise Wi-Fi design.

It all ties back into the original 2.4GHz bands used by early Wi-Fi setups. There were 11 20MHz channels available there, but many of them overlapped with each other, so to avoid multiple access points interfering with each other, the industry standardized on using the three channels that had no overlap. Hence, access points with overlapping coverage would be tuned to a different one of the three channels for interference-free connectivity.

The three-channel system is still an industry standard, so the addition of a third usable 80MHz channel means that 80MHz channels can be used much more widely. (There’s technically room for six 80MHz channels within existing unlicensed bands, but four are constrained by dynamic frequency selection rules, meaning that they have to coexist with licensed users and aren’t suitable for use in many cases.) Those are capable of gigabit speeds in ideal conditions, but even in the real world, they should provide far faster connectivity than 40MHz channels, according to Chuck Lukaszewski, vice president of wireless strategy and standards at HPE-owned Aruba.

“80Mhz is sort of a magic number because everything these days is about gigabit, and it’s the minimum channel size to get to one gigabit,” he said.  “So the FCC decision basically gives us an extra gigabit-capable channel.”

The hardware makers are eager to cast the decision, and similar ones around the world, as forward-looking public policy decisions, not just a windfall for their technology.

“Regulators around the world…have made a policy decision that making more unlicensed spectrum available is advantageous to their economies from a GDP prospective and a consumer broadband access perspective,” said Lukaszewski.

Friday echoed this sentiment, calling the 6GHz move, in particular, “the next generation of unlicensed innovation.”

New services and use cases are hotly anticipated for the new world of Wi-Fi, even if they mostly remain in the planning stages at this point. Augmented reality systems, projecting information onto real-world situations to provide remote assistance and troubleshooting or even remote surgery is one much-hyped possibility, according to Friday. High-bandwidth connections orchestrating the movement of robots in warehouse and supply-chain settings is another, said Lukaszewski.

Even if the brand-new uses for Wi-Fi are still largely just bright ideas at present, the core advantages are clear: Wi-Fi 6E and its successors will continue to ramp up real-world connection speeds into the gigabit range, and they will do it sooner, rather than later.