You have probably known about 802.11n for a while now, that’s the protocol where 5GHz was introduced to the WiFi environment, then its successor was implemented, 802.11ac and everyone went crazy about this new and improved protocol.
One of the biggest improvements was the wider channels. This meant that we could get almost double the throughput than before. There were also performance upgrades with higher-order modulation of 256-QAM, combined with the wider channels, yielding a data rate of up to 866Mb/s per channel in the 5GHz band.
This is also where beam-forming was standardized, where the radio signals are transmitted in such a way that they are directed to a specific device. This can be done with smart antennae that physically move and track the device or through modulating the phase and amplitude of the signal thus they will destructively interfere with each other to form a narrow beam.
This meant for even better throughput and a lot of power saving.
But even then WiFi was never perfect, since the beginning of WiFi it has work in the same way, think of it as the wooden wheel, it led to great discoveries. We could make the wheel thinner thus making it faster, but at the end of the day – it was still a wooden wheel.
To understand this, we need to dig a little deeper into how WiFi worked up until 802.11ac.
WiFi was already fast at this point, but the biggest flaw that it had, was that it could only talk to one device at a time. This was done really fast but still could only communicate with one device at a time. It would give the entire bandwidth to that device when communicating with it and ignores all other requests, all this happened in microseconds so the end user wouldn’t know about this delay, but nonetheless, it was still a major flaw.
Imagine WiFi packets as cars, with 802.11ac and below, the car gets the whole highway to itself, there are no lanes and only one car is allowed on the highway. This car is travelling at nearly the speed of light, but, imagine this highway with lanes and cars that can travel in both directions. Now we can fit as many cars as we need and each car gets a perfectly sized lane for its purpose and all similar cars are right behind it. There would be bigger lanes for bigger cars.
That is exactly how 802.11ax or WiFi 6 works. It does this with OFDMA (orthogonal frequency division multiple access) basically it is frequency division multiplexing.
With OFDMA, each channel can now be sliced into many other sub-channels, each with their own frequency. The signals will then be phased at right angles or orthogonally, so they can be stacked on top of each other and the de-multiplexed.
This now means that each channel can handle up to 30 devices at a time. The 2.4GHz and 5GHz can be combined to create new channels as well.
That’s not all WiFi 6 has to offer, an improvement in the power division came along with it. It is called wake time scheduling. With this, the access point can tell the device to sleep and it would provide a schedule of when to wake again. These sleep periods aren’t long but if you add up all the sleep times, it will make a significant battery life improvement.
This protocol also came with all the normal upgrades of wider channels and faster processing. The modulation has been upgraded to 1024-QAM as well.
The theoretical speed of WiFi 6, if all bands and channels were to be allocated to one device, is up to 10Gb/s. That is almost 10x faster than WiFi 5 ( 802.11ac ).
Router manufactures started selling WiFi 6 routers in early to mid-2018. The first phone to support WiFi 6 is the Samsung Galaxy S10, S10e and the S10+.
How do you know if you’re connected to WiFi 6?
You will see the WiFi 6 logo as shown here.
So, what does all this mean now? Well, we have just invented the rubber tyre and there are many years of exploration and innovation to come to fully utilise this new protocol.