Wi-Fi 6 is barely here, but Wi-Fi 7 is already on the way
Originally Appearing in https://www.cnet.com/
Author: Stephen Shankland, September 3, 2019
With improvements to Wi-Fi 6 and its successor, Qualcomm is working to boost speeds and overcome congestion on wireless networks.
Wi-Fi 6 is just now arriving in phones, laptops and network equipment. But engineers are already turning their attention to what’ll come next: Wi-Fi 7. With speeds as high as 30 gigabits per second, the next generation of Wi-Fi promises better streaming video, longer range and fewer problems with traffic congestion.
The change will come in a series of steps, beginning with improvements to Wi-Fi 6, that lay the groundwork for the expected arrival of Wi-Fi 7 in 2024.
“I’m excited about delivering a gigabit everywhere in your house, every nook and cranny,” said V.K. Jones, Qualcomm’s vice president of technology. “You’ll be at the point where wireless is faster than wired.”
In a talk and subsequent interview at Qualcomm’s Wi-Fi Day in August, Jones shared some details on how Wi-Fi 7 will work. He expects three phases of improvements over today’s Wi-Fi 6, which in technical circles is called 802.11ax.
The first expected improvement will give Wi-Fi 6 more capacity, with new airwaves that US and European governments are likely to open up for radio transmission as soon as next year. Second, an update to Wi-Fi 6 in 2022 should improve its speeds, especially for people uploading data like videos from phones or PCs. Third, and perhaps most interesting, is a collection of Wi-Fi upgrades expected in 2024 and still known only by its technical name of 802.11be.
Nobody’s quite ready to officially call that new version Wi-Fi 7. That includes the Wi-Fi Alliance, the consortium that comes up with the numbers and bestows its Wi-Fi logo on products that pass its certification tests. Heck, its program to certify Wi-Fi 6 products only begins later this year.
Still, you don’t have to be a soothsayer to see this future. The last three Wi-Fi engineering standards — IEEE 802.11n, 802.11ac, and 802.11ax — have been certified as Wi-Fi 4, 5 and 6, respectively. So 802.11be is a strong candidate to receive the Wi-Fi 7 label.
The Institute of Electrical and Electronic Engineers, which develops the 802.11 standards that the Wi-Fi Alliance later certifies, is already at work on 802.11be. It’s the IEEE working group that proposed the 30Gbps speed in its project authorization request. For comparison, CNET’s tests so far have shown Wi-Fi 6 delivering a maximum of 1.3Gbps. The working group also seeks to reduce communication delays to improve performance for latency-sensitive activities like gaming.
First Wi-Fi improvement: 6GHz airwaves
The first big change is likely to come from governmental largesse. Today’s Wi-Fi uses two radio frequency bands: 2.4GHz and 5GHz. The US and Europe, though, are working on releasing a huge new swath at 6GHz.
“This is very juicy real estate,” Jones said of the new spectrum, predicting that it’ll quadruple speeds when you’re at work or watching a game in a stadium.
The only way devices will be allowed to use this frequency band is through Wi-Fi 6 and later versions of the technology. That means older devices won’t gum up the works. “You don’t have all these crap legacy devices hanging around that don’t really know how to share,” said Kevin Krewell, an analyst at Tirias Research.
One problem: Some telecommunications companies already use parts of the 6GHz band in specific locations. Fortunately, network engineers know where those beams run and can work around that with what amounts to a fancy map called the Automated Frequency Coordinator, or AFC.
Convincing the government this system works will be the biggest challenge for opening up the 6GHz band, says Rishi Grover, a senior director at network equipment maker CommScope.
But Jones is confident it’s a solvable problem. “We’re used to dealing with sharing spectrum,” he said. “It’s up to us to convince ourselves and the rest of the world we can protect these incumbents.”
Of course, the 6GHz spectrum will eventually fill up with traffic, too, Endpoint Technologies analyst Roger Kay predicted. “They all talk about 6GHz as the wide open spaces: ‘You can just let your cattle run wild out there.’ The reality is that contention will fill the channel just like every other one over time,” Kay said. “Still, it’ll be nice for a while.”
Phase two: Wi-Fi’s uplink upgrade
In 2022, another change should come to today’s Wi-Fi 6, delivering promised features of 802.11ax. Specifically, expect a triple-whammy acronym, UL MU-MIMO. That stands for uplink multiuser multiple-input multiple-output. Whew!
MIMO, already built into Wi-Fi 4 and 5, takes advantage of the fact that radio transmissions sent from one device to another often take multiple paths, bouncing in different ways off things like walls, furniture and cars. By sending different data over different paths, you can get more out of the existing airwaves.
Wi-Fi 6’s first phase, arriving now, brings the multiuser upgrade, MU-MIMO, which means an access point can beam MIMO data to several devices at once. The second uplink phase will speed devices uploading data to the network.
At Qualcomm’s Wi-Fi Day, the company demonstrated UL MU-MIMO with 10 phones livestreaming a woman painting a colorful landscape. The three phones that supported UL MU-MIMO sent an uninterrupted video of her brush strokes, while the video from the other seven phones often paused for seconds at a time.
Phase Three: Wi-Fi’s better beams
That brings us to 802.11be, the Wi-Fi 7 contender likely to arrive in 2024 with another improvement to MIMO.
It’s called coordinated multiuser MIMO, or CMU-MIMO. “It’s very hard to get it to work, and it may not even make it,” Jones said, but if it does, expect another boost to Wi-Fi speed, range and traffic decongestion.
Wi-Fi 6’s MU-MIMO lets network equipment makers build access points with an eight-antenna arrangement, but 802.11be will handle 16. And that opens the door for CMU-MIMO.
The “cooperative” part of CMU-MIMO comes because all those antennas need not necessarily be on a single access point, Jones said. To improve coverage across bigger houses and businesses, the Wi-Fi industry is moving toward mesh networks with multiple access points.
Dividing those antennas among different devices would mean a better ability to send different data in different devices — “spatial resolution,” in network parlance — and thereby increasing the overall network performance, Jones said. You could imagine two access points with eight antennas each, or four access points with four each.
“When they work together they can get more out of the spectrum,” Jones said. “Spectrum is the lifeblood of all wireless systems.”
Other 802.11be changes
Also on tap for 802.11be is the ability to send data on multiple frequencies at the same time.
Today’s networks send data to devices using either the 2.4GHz or 5GHz bands. 802.11be will be able to use two bands at once and maybe all three, Jones said. That’s like holding three phone conversations at once — hard for a human, but not such a big deal for computers.
Then there’s an upgrade that squeezes more information into a radio signal. It’s called 4096-QAM, an improvement in quadrature amplitude modulation, a signal-handling technology. Wi-Fi 6 uses 1024-QAM. Bigger is better.
But speeding up Wi-Fi by pushing the limits of physics and engineering is tough, and Jones isn’t making any promises about what’ll actually arrive.
“We all have been through this rodeo many times,” Jones said. “We know how hard it is to get this stuff to work.”