Introducing 6 GHz into WiFi

WiFi is already the most successful deployment of spectrum ever. In the recent Annual Internet Report, Cisco predicted that by 2022 that WiFi will cross the threshold and will carry more than 50% of global IP traffic. Cisco predicts by 2023 that there will be 628 million WiFi hotspots – most used for home broadband.

These are amazing statistics when you consider that WiFi has been limited to using 70 MHz of spectrum in the 2.4 GHz spectrum band and 500 MHz in the 5 GHz spectrum band. That’s all about to change as two major upgrades are being made to WiFi – the upgrade to WiFi 6 and the integration 6 GHz spectrum into WiFi.

The Impact of WiFi 6. WiFi 6 is the new consumer-friendly name given to the next generation of WiFi technology (replaces the term 802.11ax). Even without the introduction of new spectrum WiFi 6 will significantly improve performance over WiFi 5 (802.11ac).

The problem with current WiFi is congestion. Congestion comes in two ways – from multiple devices trying to use the same router, and from multiple routers trying to use the same channels. My house is probably typical, and we have a few dozen devices that can use the WiFi router. My wife’s Subaru even connects to our network to check for updates every time she pulls into the driveway. With only two of us in the house, we don’t overtax our router – but we can when my daughter is home from college.

Channel congestion is the real culprit in our neighborhood. We live in a moderately dense neighborhood of single-family homes and we can all see multiple WiFi networks. I just looked at my computer and I see 24 other WiFi networks, including the delightfully named ‘More Cowbell’ and ‘Very Secret CIA Network’. All of these networks are using the same small number of channels, and WiFi pauses whenever it sees a demand for bandwidth from any of these networks.

Both kinds of congestion slow down throughput due to the nature of the WiFi specification. The demands for routers and for channels are queued and each device has to wait its turn to transmit or receive data. Theoretically, a WiFi network can transmit data quickly by grabbing a full channel – but that rarely happens. The existing 5 GHz band has six 80-MHz and two 160-MHz channels available. A download of a big file could go quickly if a full channel could be used for the purpose. However, if there are overlapping demands for even a portion of a channel then the whole channel is not assigned for a specific task.

Wi-Fi 6 introduces a few major upgrades in the way that WiFi works to decrease congestion. The first is the introduction of orthogonal frequency-division multiple access (OFDMA). This technology allows devices to transmit simultaneously rather than wait for a turn in the queue. OFDMA divides channels into smaller sub-channels called resource units. The analogy used in the industry is that this will open WiFi from a single-lane technology to a multi-lane freeway. WiFi 6 also uses other techniques like improved beamforming to make a focused connection to a specific device, which lowers the chances of interference from other devices.

The Impact of 6 GHz. WiFi performance was already getting a lot better due to WiFi 6 technology. Adding the 6 GHz spectrum will drive performance to yet another level. The 6GHz spectrum adds seven 160 MHz channels to the WiFi environment (or alternately adds fifty-nine 20 MHz channels. For the typical WiFi environment, such as a home in an urban setting, this is enough new channels that a big bandwidth demand ought to be able to grab a full 160 MHz channel. This is going to increase the perceived speeds of WiFi routers significantly.

When the extra bandwidth is paired with OFDMA technology, interference ought to be a thing of the past, except perhaps in super-busy environments like a business hotel or a stadium. Undoubtedly, we’ll find ways over the next decade to fill up WiFi 6 routers and we’ll eventually be begging the FCC for even more WiFi spectrum. But for now, this should solve WiFi interference in all but the toughest WiFi environments.

It’s worth a word of caution that this improvement isn’t going to happen overnight. You need both a WiFi 6 router and WiFi-capable devices to take advantage of the new WiFi 6 technology. You’ll also need devices capable of using the 6 GHz spectrum. Unless you’re willing to throw away every WiFi device in your home and start over, it’s going to take most homes years to migrate into the combined benefits of WiFi 6 and 6 GHz spectrum.

One thought on “Introducing 6 GHz into WiFi

  1. What are the technical possibilities for using WiFi 6 like a freeway, in that the new routers could send and receive old WiFi like onramps to the traffic between WiFi 6 devices? Alternatively, could WiFi 6 provide “backhaul “ to more localized “old WiFi” traffic?

    Like

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