6GHz Spectrum, The Future of Wi-Fi
In today’s training video, we were talking about the new 6GHz spectrum. 12000 megahertz of new channels for us, this is going to be the future of Wi-Fi.
Transcription
In today’s training video, we’re going to be talking about the new 6 GHz spectrum, 1200 MHz of new channels for us. This is going to be the future of wifi.
In today’s video, we’re talking about 6 GHz spectrum, 1200 MHz of new channels for us. That is such a huge chunk. It’s more than double of what we had before. The future of wifi is in 6 GHz.
Like we’ve done in the other videos on the other bands, we can look and compare the difference between 2.4, bigger waves, 5 gig, smaller, and then 6 gig, slightly smaller than that. They’re smaller waves. It means a couple of things. One are antennas to have them tune properly, are tuned to the frequency, which also means that the antennas receive aperture. The size of the radio wave they’re tuned to get will collect more or less RF energy.
The 2.4 waves have a big circle and they collect 4.9 inches, 12 centimeters or so worth of data. So when they are listening, those antennas hear more RSSI, a lot more, around 6 dB differential, just because I have a bigger aperture. 5 gig and 6 gig are fairly close. There’s a slight difference between there, not nearly as much as the difference between 2.4 and 5 gig.
So a lot of times people say something that’s totally wrong, like 5 gig doesn’t go as far as 2.4, and that’s a total lie. 2.4 and 5 gig go the exact same distance. If I have a radio that transmits to the same power, the energy goes the same way, all the way to the moon, all the way to Jupiter, all the way to Alpha Centauri. They both go the same distance. The difference is all about receive aperture. If I have a 5 GHz receive aperture that’s smaller, it receives 6 dB less energy than the 2.4. So what you should be saying is the 5 GHz receives 6 dB less at a given distance than 2.4. The radio waves go the same, but there’s a less distance because of the receive aperture. You can offset that by just increasing 6 dB on the transmit power of the 5 gig or taking the 2.4 down by 6 dB. We can make them equal. We just need to understand how it works.
Now, we can also look and see that 6 GHz has 1200 wonderful megahertz of us to play with. Well, here’s the issue. Depending on the country you’re in, you may or may not get all of this, and depending on the usage that you want for yours, you may or may not get the same amount, in the same number.
This graphic is… By the way, this is done… Sorry, I’m an Excel guy, this is done in Excel. All the little numbers inside are just formulas, and so it’s a repeatable thing. You can go in and edit it. And so this is just showing us in this graph, the difference between FCC and ETSI, the EU. Those are the only two that we have data now. A couple of other kinds countries have already jumped on board and coming fairly quickly. They haven’t codified those yet, so I haven’t added them to the chart. In between these two, there’s one that says Standard Power. The top ones says Low Power. The next one down says Standard Power. And even on this screen, even if you have a high def screen, that’s a lot of information to squeeze. It’s pretty wide. So let’s zoom in and look at these differently.
First up, we’re going to look at just the US alone. What I’ve done is I’ve broken this big long 1200 MHz into two chunks so they fit on the screen a little better, but they go together. So we have our U-NII-5, that’s the ones in blue. U-NII-6 is in green, U-NII-7 is in yellow, and then kind of a burnt orange or something for U-NII-8. This is the entire 6 GHz spectrum. There is, by the way, if you look on the far left side, there’s a channel that is part of U-NII-4, but it’s not going to be contiguous. We might win back that U-NII-4 in the 5 GHz range, but we won’t have a contiguous. So there’s one that’s missing there.
If you look there, you can see Radio Band, Center Frequency, and the 20 MHz channels, like 59 of them. We have so much frequency available in 5 gig for low-power devices. Now low-power devices, for us, sounds like it’s low power. How low power is low power? Well, for wifi in the 6 gig range, it’s actually 18 dBm. That’s really decent power. There’s a lot of sites we’ve done, and we don’t even go up to 18 dBm in our transmit power. so low power is really mostly, think indoors, think what you’re normally doing. You’ll have 59 more channels. Now, one of the other issues that we have with the difference between 5 gig and 6 gig. In 5 gig, we measure off of EIRP, the effective isotropic radiated power. And so as we go to a wider channel from 20 to 40, we lose 3 dB of SNR because we have a wider channel, more noise. The noise floor, we hear 3 dB more noise, so my SNR drops.
In the 6GHz range, through the negotiations with the FCC, instead of using EIRP, they use a term called net EIRP, which means it’s going to be consistent. So if we went from a 40 to an 80, the rules allow the louder transmit power, so the net EIRP stays the same as we go. So the net is the 18 dBm, meaning we can actually, as we go to wider and wider channels, transmit a little louder to offset that noise differential, meaning we can keep that 18 dB EIRP at 20, at 40, at 80, which means there is no penalty for going to wider channels.
And since we have so many of them, we can follow the rule, which is use the widest channel you can until you can’t. You can’t is when you have co-channel interference. Well, if I have twelve 40 MHz channels just in the U-NII… Sorry, my brains here. If we have 12 just in the U-NII-5 alone, well, I can go without co-channel interference. So what used to be 40s were pretty normal in 5 gig, we can now look at 80s will give us the same range in the 6 gig range.
So for the US, these are the rules. If you look at the second thing down, it says Standard AP Power. This is not low power. Standard power, in this case, goes up to 36 dBm, pretty loud, specifically for outdoors. In order to protect the incumbents, the people who are currently using the 6 GHz range, the FCC did some negotiations. And we came up with the answer saying, “If you’re in this range, if you’re in U-NII-6 or U-NII-7, you can’t use all of the channels the same way you used to be able to use them.”
So if you look down here, you say, “Oh, U-NII-6 now, which we could’ve used in low power, all these little channels, 97, 101, 105. Yeah, we can’t use those at all in U-NII-6,” which also means the U-NII-6 penalty of this channel 113, since we can’t use that channel specifically, it means in U-NII-7, we lose our channel 117 as well, because it would’ve bonded across that line. So we lose the 40 and the 80 and the 60. So U-NII-7 is basically losing it from both sides because of the fact we can’t use U-NII-6 or U-NII-8. U-NII-5 is fine across the board, we’re great there. If we’re going to be using U-NII-6 or 7 or 8, we need to be cognizant of that outdoor transmit power issue. We have fewer channels to play with there.
That’s for the FCC in the US. Let’s look what’s going on in the EU. That’s what’s going on in the FCC in the US. Let’s look back at the EU. The EU, and we’ll zoom in here to just the EU chunk here. They’re only picking up the U-NII-5. U-NII-6, 7, and 8 is US only. Perhaps maybe after some additional negotiations, other countries, other regions in the world will get those. But for the beginning, EU is working on releasing the U-NII-5 band. Hey, there’s still 24 new channels. That’s half a gigahertz of frequency for us to play with. Even in the EU, we’re going to be looking at these. EU is only low-powered only for now, but it still has lots and lots of capabilities.
We talked about some of the issues in 6 GHz today. 6 GHz is going to be the future of wifi. I think it’s great that we’re moving that direction. If you need any more information, you know where to go, wlanpros.com, tons of information there. We love sharing with the community. Thanks for being part.
