What Wi-Fi 6 Brings to the Industrial Sector

It need not be said that the world now completely depends on wireless technology. Every 4-6 years we see a new version of Wi-Fi, each bringing with it heightened speeds and capabilities, but the more a technology can handle, the more it will be pushed to its limits. Upon its release in 2013, Wi-Fi 5 (IEEE 802.11ac) brought with it higher bandwidths, multi-user MIMO, higher number of spatial streams, and a higher number of modulation schemes, and for eight long years it has coped with the increasing number of connected devices and commonplace communication requirements. But as we are moving towards complete wireless autonomy in both the industrial and commercial sectors, the world is ready for another upgrade.

Before we get onto the interesting new features of Wi-Fi 6, let’s get the basics out of the way. Obviously, an upgrade wouldn’t be an upgrade if the numbers weren’t improved — Wi-Fi 6 brings with it lower latency, greater speed, and greater capacity — and it is the impact on the industrial space that these areas of improvement bring which is significant.

Latency
In simple terms, Latency is the time it takes for data to travel from point A to point B. The lower the latency the quicker the response time, and Wi-Fi 6 brings a 75% reduction in latency over Wi-Fi 5. In commercial environments having a lower latency could be viewed as a quality-of-life improvement, perhaps allowing for faster communication with smart home devices, but in the industrial sector having a lower latency can literally mean the difference between life and death. Machinery on the factory floor, wirelessly connected to a central control room, needs near-instant communication with safety mechanisms to ensure timely responses to any mechanical failures. With lower latency, remote security systems will be able to stream 4K video over wireless connection with minimal delay, allowing operators to make decisions in real-time and take more timely action. Lower latency in industrial environments can save money, reduce risk to personnel, and open doors to technologies and processes which were perhaps unachievable with Wi-Fi 5.

Speed
Wi-Fi 6 offers a theoretical maximum throughput of 9.6 Gigabits per second (1.2 Gigabytes per second) — three times that of Wi-Fi 5. Not only will existing wireless devices be able to transmit large data faster, but increased Wi-Fi bandwidth opens the door to connecting devices to the network which may have previously been cost-prohibitive. For instance, a factory could have machinery in outbuildings which they wish to update with complex monitoring systems, with a view to communicating the large amount of information gathered by sensors back to the central control room. The cost to hard-wire these outbuildings with Ethernet may deter the company from making the investment, but Wi-Fi 6 would theoretically allow for wireless connectivity via much more cost-effective access points, with only marginal difference in transfer speeds between that and a traditional network.

Capacity
When it comes to wireless connectivity, the term ‘capacity’ indicates the number of connected devices that a wireless access point (AP) can support, and Wi-Fi 6 is geared up to alleviate network congestion by increasing this capacity over Wi-Fi 5. Furthermore, Wi-Fi 6E, or High-Efficiency Wi-Fi, is said to accommodate 14 additional 80 MHz channels and 7 additional 160 MHz channels. These additional channels are needed for high-bandwidth applications, such as wireless 4k streams to digital signage devices and virtual reality applications in the industrial and commercial spaces, and with Wi-Fi 6E delivering upwards of 1200 MHz of spectrum (for unlicensed use) in the 6 GHz band, it offers four times the capacity of Wi-Fi 5 which delivers via 2.4 and 5 GHz bands just 400 MHz of unlicensed spectrum.

Aside from the improvements over Wi-Fi 5 in the areas of latency, speed, and capacity, Wi-Fi 6 introduces a few new features, and builds on technology from Wi-Fi 5 to further improve the performance of wireless connectivity.

MIMO
MIMO isn’t a new feature per se — we’ve enjoyed MIMO technology since Wi-Fi 5 introduced it back in 2013 — but Wi-Fi 6 stands on the shoulders of what Wi-Fi 5 developed and takes it to the next level.

MIMO, or multiple input, multiple output, is an antenna technology designed to minimise errors, optimise data transfer speed, and improve the capacity of wireless transmissions. MIMO enabled networks have multiple antennas at either end — both at the source (AP) and at the end point (connected device) — and use these antennas to combine signals, creating a much more stable signal by providing more opportunities for the data to reach its destination without fading, as the signal-to-noise is improved and congestion relieved.

Where Wi-Fi 6 comes into its own is the direction in which MIMO data can be transferred. Wi-Fi 5 is able to transmit data via MIMO from the AP to the connected devices, whereas Wi-Fi 6 can also use this technology from the device back to the AP. This is particularly significant for the industrial sector where devices transmitting large amounts of critical data need stable connections and uninterrupted transmissions to perform their function efficiently.

Spatial Frequency Reuse (SFR)
A common issue with environments containing multiple access points is that an AP’s performance can be affected by completely irrelevant data from other APs. A wireless transmission will pause for any request for connection, even for connections made to a different AP by a device connected only to that AP. SFR is set to change that, by assigning “colour” denotations to APs operating on the same channel, so that they can differentiate between transmissions intended for them and others they can disregard.

Improved Scheduling
With Wi-Fi 5 there is the danger that two devices using the same channel can try to access the same uplink resource, causing conflicts and therefore delays and connectivity issues. With the increased capacity of Wi-Fi 6 this potential issue is further compounded, so as part of the development of Wi-Fi 6 the scheduling of uplink resources has also been addressed. Now, should a conflict occur, Wi-Fi 6 schedules the uplinks more effectively, immediately giving each uplink its own slot to avoid transmission blocks and drops in connectivity.

Target Wake Time / Wi-Fi Sleeping
This one is a little more self-explanatory — Wi-Fi 5 connected devices, should they be connected to an AP, will maintain that connection even when there is limited demand. Wi-Fi 6 uses target wake time protocols to drop dormant connections and put the relevant devices themselves to sleep, thus reducing the number of connections competing for bandwidth and preserving the battery life of remote devices.

One important note for those in the industrial sector looking to adopt Wi-Fi 6, is that Wi-Fi 6 serves ac, n, g, b, & a protocols, meaning any device supporting these protocols can communicate with a Wi-Fi 6 enabled AP. A caveat, though, is that older standards like 802.11b can create bottlenecks on the network which can impede some of the performance gains outlined above.

Despite its many improvements, Wi-Fi 6 still uses the same radio technology as Wi-Fi 5, so the existing problem of signal penetration will remain. That being said, there are many ways to combat this issue, with one of Impulse Embedded’s customers doing just that with an Advantech LPWAN solution. Read more about that here.

Wi-Fi 6 is obviously a major upgrade from its predecessor in latency, speed, capacity, and features. It should be relatively painless for companies to make the switch and, with the backwards compatibility, rollout can be done in phases rather than being a large, single undertaking. If you require more information, or would like advice or hardware solutions to make the switch to Wi-Fi 6, you can get in touch with Impulse Embedded’s IoT Specialists on +44(0)1782 337 800 or click here to submit an enquiry.