WiFi 6 for industrial and logistic IoT

Probably one of the most discussed topics today around Wi-Fi technology is the emerging of the shiny new Wi-Fi 6 standard, or in the official name 802.11ax. So what is it about this new standard that making so much buzz in the market? Well, everything.

Even before ratifying the final standard vendors started shipping wifi6 pre-standard access points, the first one was Huawei back in 2017, Aerohive came next with their AP630 model. Today almost every vendor has his flagship 802.11ax access points. That being said, remember it needs two to dance the tango; on the client-side, there are only a few devices support the new standard, although with major mobile phone companies joining the race (Samsung, Apple), the future of Wi-Fi 6 is looking more realistic.

If we have a look at the traditional industrial players, like Siemens, they still haven't announced their 802.11ax portfolio yet, but I'm quite sure deep in their labs, something is being cooked.

The business case of industrial IoT

It's not a secret that the era of economic growth we live in is driving us to consume more goods; this demand is adding a significant load on farmers, manufacturers, and suppliers. And here, where IoT (in my opinion) will reflect the technology's highest values.

Almost every aspect of manufacturing, efficiency and automation are required to increase productivity and reduces costs. A swarm of sensors and connected devices are helping to get a better picture of the production process, machine maintenance, down-time and inventory status. These sensors have to be somehow connected to be able to share this data with other data analytic systems.

Here are some of the advantages of Industrial Wi-Fi, compared to 4G/5G cellular technology:

• Relatively easy to deploy
• It doesn't require a license to operate in the 2.4GHz and 5Ghz frequencies.
• Wi-Fi can be entirely managed by the organization's IT teams without relying on third-party operators.
• Most importantly, it comes with a relatively decent price tag for both infrastructure and client devices.

Understanding the fundamental operation of Wi-Fi

Wi-Fi is an undetermined network access technology; hence, each device has to listen to the network and transmit only when the medium is free. Listen before talk (LBT) is a protection mechanism that is regulating access to the network to assure successful data transmission. However, this mechanism is also adding delays in a busy system.

It is crucial to understand the concept of LBT because it defines how Wi-Fi works. Keeping in mind the most important resources in the Wi-Fi communication is the airtime, and how fast we deliver the data from a client to the Access point and vice versa. At every given time, there is only one talker in the Wi-Fi network; the rest of the devices have to listen and wait for their turn to talk.  

What about the speed?

While all the previous Wi-Fi standards were focusing primarily on achieving high data rates, Wi-Fi 6 comes with a refreshing, welcoming approach, and the new standard is there to increase the overall technology efficiency. 

here are some of the critical success points for Wi-Fi 6 when it comes to IoT, a short review in a simple language  

OFDMA - perhaps the major anticipated feature of Wi-Fi 6, in a nutshell, OFDMA sub-divides the frequency into smaller parts called resource units, allow multiple devices to transmit and receive simultaneously. Unlike today's Wi-Fi (802.11a/b/g/ac), where one client transmits on the whole channel in a given time. This method increases efficiency and reducing delays; network delays might, in some cases, lead to halting the production process in the factory. 

TWT - Target Wake Time is a mechanism that allows the Access point and the client to negotiate the power save time. Long battery life is vital for IoT devices, which are designed to last few years without the need for changing the battery. Think of a temperature sensor in a warehouse where it needs to report the temperature of shelf X twice a day; this sensor can wake up, sends its reading, and go back to sleep for the next 12 hours. 

BSS coloring - is another exciting enhancement that comes with 802.11ax standard. Potentially it can reduce interference if it happens due to channel occupancy by another access point or transmitter.

Eventually, Wi-Fi 6 brings multiple other enhancements to the current Wi-Fi standards. Even older generation devices will benefit from this technology, the more efficient the network is, the less time the air time is occupied will improve the wait-to-transmit time for all the devices.