The IoT is a fragmented technology landscape, with many wireless communications options. But the number one question Cees Links, an expert in wireless technologies and General Manager of Qorvo gets from engineers, is “Are Wi-Fi 6 and 5G compatible?”
FierceElectronics spoke with Links about the two wireless options, why they are complementary--not competitive—and during the interview we got a bonus history lesson!
FE: So, you get this question all the time about whether Wi-Fi 6 and 5G can work together or whether one will ultimately cannibalize the other. What’s your typical response?
Cees: Well, to understand the answer to that question you really have to go back to the beginning. The history of these two technologies and how they got to where they are today is something you could write a book about! Now bear with me because you are going to wonder what in the heck I’m talking about, but have you ever compared the keypad of your phone with the keypad of your calculator? The keypad of your phone as you can see is 1-2-3 4-5-6 7-8-9. On the calculator, it’s the same, only upside down.
That keypad design is rooted in ATT and Bell Labs—both were in the telephone world and cellular world. It’s all ruled by what you could call the ties and the suits of the corporate world that leads straight from that keypad to the phone to the cellphone to 3G and beyond.
The Wi-Fi world is one made up more of what I’d call the renegades of the time—IBM, TI, Cisco. These computer guys, they built their own world and that world included networking and Wi-Fi and you know they really come from a different gene pool and different constitution.
Along the way, cellular and Wi-Fi developed their own ecosystems and their own strengths. So, in the end, there isn’t one best solution that will dominate the other. They both filled a need and they filled a space and they became very good at that and they will be sticking there for a while.
FE: So, no world domination for either?
Cees: Not for lack of trying, or at least wishing that would be the case! In 1998 when I was working for Lucent, the world was getting ready for 3G and my boss told me that the world did not need Wi-Fi. 3G was going to be 3 Mbps and who needed more than that! Meanwhile, Apple had just adopted Wi-Fi for the iBook and they were rolling it out. Lucent was saying that was just a temporary blip, that 3G would take over the world. While that didn’t happen and Wi-Fi started to make some real waves, and then everyone said that 4G would come out and wipe Wi-Fi from the face of the Earth.
Then 4G came out and I can point to one particular application domain where it won over Wi-Fi, but it is not very well known in the US . In Europe we use a lot of trains and there was a strong impetus to get Wi-Fi on them. The reality is that it was never really successful. The connection from the train to the backhaul to the Internet was so crappy and 4G provided a way better experience. So, everybody is using 4G as a hot spot when riding the train.
That was an application where 4G gained some territory on Wi-Fi, but in reality the boom in wireless usage was so intense that 4G and Wi-Fi started living together and producing capacity that was required to handle all of the traffic. About 60% of the traffic is handled by Wi-Fi and 40% goes over 4G. If you just imagine all the Wi-Fi traffic having to go over 4G, then it shows immediately we would be dealing with another problem: The scarcity of spectrum. In reality, Wi-Fi and 4G have to work hand in hand.
FE: What are the key differentiators?
Cees: In a nutshell, cellular is the designated choice for outdoor networks. The cellular world is mobile, it’s SIM cards, a subscription model, and a service. With 5G providing speeds up to ten times higher than 4G, more devices per cell, and new options for private communications, it is going to open up even more new use cases.
Wi-Fi will continue to be the access choice for indoor networks. It has no SIM card, and it is an unlicensed spectrum that is as good as you can get because it was developed for inhouse usage in the same way 5G is superior for outdoor usage. With the improvements in speed, latency and an ability to handle higher number of connected devices, Wi-Fi 6 is going to be perfect for indoor enterprise networks.
FE: Give me an example of how they’re working together?
Cees: Consider the smart phone, which has three radios. One radio is for outdoor, which is the 5G radio, one is the Wi-Fi radio, and one is a Bluetooth radio. Your Bluetooth radio is like your personal bubble that you carry around as you go from place to place.
If you think about this design, normally customers don’t care whether it’s Wi-Fi or 5G or Bluetooth, what they care about is a seamless experience to be able to run the applications they want. Whether or not these technologies go down a path of convergence is sort of irrelevant, what matters is that they continue to provide that seamless experience to the customer.
FE: Isn’t a hassle for developers to have to cram multiple radios into a device?
Sees: Well, it’s being done successfully today. As an engineer myself, I can see that it’s a challenge, but I also imagine it’s kind of paradise for many of them. There are so many ways to bring all these radios together in a compact footprint and achieve good range and power (without overheating!) that I would imagine one can really show off their prowess as an RF engineer. All you have to do is pick up an iPhone and marvel at all the brilliant technology and engineering that went into making one.
FE: What are some of the recent developments and what does the future hold?
Cees: One of the biggest developments this year was the expansion of the Wi-Fi spectrum. What happened is that the Trump administration came in and said, “If you look at the economic value of W-Fi, it is factors larger than the economic value of 3G and 4G and 5G, so why have we not increased the spectrum for Wi-Fi?” Conversely, the spectrum for cellular networks had been increased 2 to 3 times over the last two decades.
So, the FCC really created the momentum to expand the spectrum for Wi-Fi. It almost tripled, giving Wi-Fi a lot of oxygen for the next generations. Looking ahead, the IEEE and industry are working on the standards needed for Wi-Fi 7, and the spectrum is available for Wi-Fi 8. The most amazing thing we are dealing with is that the newest generation of Wi-Fi is doing roughly 10 Gbps. In 20 years, the speed has increased by a factor of 1,000 and that is indicative of how popular you know wireless is in general.
On the cellular side, you see something similar, although by a factor of hundreds, and we’re going to see 6G and 7G. So, these two worlds at least for a while will develop further, both individually and together.
FE: Working together again. Can you give me another example?
Cees: An interesting development is that a lot of the operators that have cellular networks are starting to appreciate Wi-Fi networks. In the past, cellular was preferred over Wi-Fi traffic because base stations in the public area are expensive to install and replace. But now the thinking is if you have a lot of WiFi infrastructure, why not use it? So, with a lot of the operators in the world, you know, really embracing Wi-Fi they have changed their tune from saying we deliver internet to your front door and what you do inhouse is your own responsibility. They have adopted the indoor networking experience and are providing a smooth indoor networking experience they consider part of their service.
That’s why all these companies are investing in leading edge Wi-Fi technologies and gateways and routers. But, you know the flip side is that even the owned Wi-Fi networks indoor and the cellular networks outdoor can now make it easier for people to switch between the two.