Qualcomm backs Wi-Fi 7 wireless standard • The Register

Momentum is gathering behind Wi-Fi 7 with Qualcomm adding its support to the new wireless standard.

Qualy says the newest iteration will drive applications such as augmented reality (AR) that need low latency, but also address contention issues in spaces like offices by making better use of the available spectrum.

Wi-Fi 7 aims to deliver twice the speed relative to current Wi-Fi 6 kit, with multi-gigabit speeds even in high traffic scenarios, higher capacity, plus lower and consistent latency for next-gen use cases, according to Qualcomm. The vendor expects to see products with Wi-Fi 7 coming to market in 2023, which is consistent with what others such as MediaTek have claimed.

However, Wi-Fi 6E kit is becoming available now, which can boost performance and reduce network contention by using channels in the 6GHz part of the spectrum.

Wi-Fi 7 kit will be based on the IEEE 802.11be standard, the draft version of which was published last year.

Andy Davidson, Qualcomm’s senior director for Technology Planning told The Register that applications such as AR virtual reality environments like the metaverse have been driving the technical requirements for Wi-Fi 7.

“That introduces challenges, where you have to deliver this extremely high throughput – which is the tagline for Wi-Fi 7 at the IEEE – but you have to deliver that extremely high throughput at sustained low latency. So an application such as VR obviously needs throughput, but you have to actually hit the latency targets to make it work,” Davidson said.

And because the bandwidth is effectively shared between all the users on a wireless network, upping the speed is crucial so that each endpoint can send and receive as much data as possible when it gets its slot of airtime.

Wi-Fi 7 pushes up the speed by increasing the modulation rate to 4K-QAM (quadrature amplitude modulation) up from the 1K-QAM used in Wi-Fi 6, and also by doubling the channel bandwidth to 320MHz. MediaTek has already said it expects Wi-Fi 7 to deliver speeds several times faster than Wi-Fi 6, with connection speeds of at least 30Gbps and possibly up to 40Gbps.

Wi-Fi 7 will also be able to support channels in the 6GHz portion of the spectrum, in addition to the existing 2.4GHz and 5GHz bands, a feature that has been tacked on to Wi-Fi 6 in the shape of the Wi-Fi 6E standard.

Other key technical advances include multi-link operation and preamble puncturing. Multi-link operation is designed to help address congestion issues by allowing a device to use more than one channel.

“Access points today will typically support the 2.4GHz channel, they’ll also support two channels in another band. So maybe two channels in the 5GHz band or as 6GHz becomes available, one in the 5GHz band and one in the 6GHz band,” explains Davidson.

“Prior to Wi-Fi 7, clients would just attach on one of those channels, and use the one that was most appropriate for the needs. But with multi-link, the client can connect to the AP on multiple channels. And it can use that to avoid congestion. So if one of those channels has traffic on it, you can use another channel and therefore you can get lower latency,” he added.

There is also more than one multi-link mode. Alternating multi-link lets endpoints swap between channels based on whichever is available, while simultaneous multi-link allows both channels to be used at the same time, analogous to the way that channel bonding works in wired Ethernet networks by aggregating traffic across the two links for double the throughput.

Preamble puncturing is intended to allow as much bandwidth as possible to be used, even in instances where an incumbent user has been allocated a frequency band that occupies a portion of the spectrum that would otherwise form a free contiguous channel.

This would traditionally prevent an AP from using this channel, but Wi-Fi 7 with preamble puncturing can stitch together the frequency bands either side of the interference.

In other words, preamble puncturing is about avoiding conflicts with existing users of the wireless spectrum. The overall bandwidth of the channel is lowered by the “punctured” amount, but this method enables a wider channel than otherwise would be available, according to Qualcomm.

Meanwhile, chip supply chain issues are likely to hamper the ability of network vendors to ship end products between now and the end of this year, according to Tam Dell’Oro, founder and CEO of analyst firm Dell’Oro.

“Everyone in the networking industry I’ve engaged with expects supply constraints to continue through 2022,” she told The Register.

Dell’Oro expects to see consumer Wi-Fi 7 network equipment products start shipping in the months before the end of 2022, while enterprise class Wi-Fi 7 kit is expected towards the end of 2023. “We expect by 2023 supply constraints should be less of a problem,” she added.

Dell’Oro previously predicted that enterprises might skip Wi-Fi 6E, as the kit is delayed by the chip supply chain issues, and by the time these are over, Wi-Fi 7 gear will be available.

However, consumer class Wi-Fi 6E products may fare better, she said. “Broadband customer premises equipment is a significant portion of the market, and if the cable operators, and telecom operators want to deploy, they buy huge volumes. A broadband operator may see Wi-Fi 6E as a way to upsell their subscribers and generate more revenue, so 6E may be a strategic move. In contrast, most enterprises don’t generate revenues from their Wi-Fi networks, so deploying 6E won’t generate more revenue.”

Despite this, Dell’Oro said that applications such as security cameras and video would work really well in Wi-Fi 6E, because of its ability to use 6GHz channels where there will be no interference from the mass of existing devices that use the 2.4GHz and 5GHz channels.

Davidson at Qualcomm said that Wi-Fi 6E is basically just an extension of Wi-Fi 6 to support the newly available spectrum, and so its arrival is falling in the middle of the usual Wi-Fi upgrade cycle.

“I think the Wi-Fi 6 to Wi-Fi 7 transition is following the similar sort of timing to that which we’ve had before. The thing that’s cutting across is the availability of that new spectrum with 6GHz,” he said. But in terms of the protocol changing in Wi-Fi 6E, that is not the case, he added.

“So the Wi-Fi 6E products are compatible with Wi-Fi 6, while the Wi-Fi 7 products will be compatible with both. So I think the industry is moving forward pretty nicely in terms of incorporating Wi-Fi 6 and then incorporating 6GHz as it becomes available in the regions,” Davidson said.

Dell’Oro said that if Wi-Fi 7 does follow on from previous rollouts, then enterprise class Wi-Fi 7 kit will start shipping in 4Q23, nine quarters after Wi-Fi 6E, and Wi-Fi 6E itself is likely to peak in 3Q24 and then decline.

“Most enterprise manufacturers told me they are not planning to refresh their entire portfolio with 6E, just a few models,” she said. ®