Thursday, April 30, 2020

FCC More Than Doubles WiFi Bandwidth Available for WiFi 6

If WiFi scares you, forget 5G cellular that's still years away, a new generation of WiFi is coming and will be here years sooner than 5G.  According to the Microwaves & RF trade magazine daily email news:
The Federal Communications Commission (FCC) has adopted rules that make 1200 MHz of spectrum in the 6-GHz band (5.925–7.125 GHz) available for unlicensed use. These new rules will usher in Wi-Fi 6, the next generation of Wi-Fi, and play a major role in the growth of the Internet of Things. Wi-Fi 6 will be over 2.5X faster than the current standard and deliver improved performance. Opening the 6-GHz band for unlicensed use will also increase the amount of spectrum available for Wi-Fi by nearly a factor of five and help improve rural connectivity.
Current WiFi activity, WiFi 5, as most of you know, is located in two frequency bands separated by a factor of (a bit over) 2.  The first, and still most widely used band is at 2.4 GHz, stretching from 2.4 to 2.5 GHz - 100 MHz of allocated channels.  The problem with that band has been that it's very busy with Bluetooth, wireless toll collection and a bunch of other services so data rates can be affected.  The newer and higher frequency band is 5.18 to 5.825 GHz, or almost 810 MHz of allocated channels and over eight times the currently available bandwidth as 2.4 GHz WiFi.  The higher frequency band has much more spectrum than the lower (and first) WiFi band, and can have higher data rate channels, too.

The new allocations from the FCC will extend the 5 GHz band up 7.125 GHz.  Instead of 810 MHz, there will be over 2000 MHz of spectrum, almost 2-1/2 times as much spectrum, allowing higher data rates and relieving the congestion of too many signals in the band.  Since this was only authorized by the FCC this week, I'd expect new WiFi routers that go to 7.125 GHz to start hitting the market by the fall. There's already WiFi 6 out there, but why not wait until you get the wider bandwidth?

The transitions to Working From Home (WFH) brought on by the Kung Flu lock downs have increased WiFi usage and put pressure on the nation's systems.  
The trend toward WFH means an explosion in the need for wireless connectivity, and that means even more reliance on Wi-Fi than ever. According to high-end Wi-Fi provider Plume Design, some 22.6 million people were active online during the workday prior to the coronavirus crisis. Now, about 46.2 million users are flooding the data pipelines.

Many of our devices and routers support the prevalent Wi-Fi 5 standard (a.k.a. “the standard formerly known as 802.11ac” now that the Wi-Fi Alliance has shifted to simply numbering the standards rather than using their unwieldy IEEE monikers; I, for one, applaud the move). But what if Wi-Fi 5’s 3.5-Gb/s maximum data rate, 256-QAM limit on subcarrier modulation, and four spatial streams can’t cut the mustard?

The Wi-Fi standard has already evolved beyond Wi-Fi 5. Wi-Fi 6 is with us and promises to alleviate the growing connectivity logjam. It offers numerous improvements over its processor: With eight spatial streams and 1024-QAM subcarrier modulation, Wi-Fi 6 now sports a maximum data rate of 9.6 Gb/s.
Personally, I think this is a wonderful development and more high speed connectivity is a Good Thing.  There are existing users of that spectrum that's being allocated to WiFi (as there almost always are) but the articles make it sound like the FCC is managing the systems to minimize conflict. 

I'm only being slightly facetious about being afraid of WiFi, I know some people are.  Personally, I'd rather have everything in my house wired for gigabit Ethernet but that's for security, not concern over RF.  Chances are that people afraid of WiFi won't be affected by this because they won't have a WiFi router in their house of any kind!


  1. That's good news. More bandwidth is better. And I'm not concerned about people spying on me.

  2. More electric usage. Just what my power bill needs. Waitaminute - if the unlicensed wattage restrictions remain the same, then these things are going to have about half to one third the range. Except that they're not competing against much in that band. For now.

    Odd, isn't it, how Cali keeps saying we all need to use less power, then they invent more and more gadgets (electric cars, etc.) that require more and more electricity?

    1. Waitaminute - if the unlicensed wattage restrictions remain the same, then these things are going to have about half to one third the range.

      The range probably will go down but how much is complicated. There's an inverse relationship between range and wavelength. At 5.8 GHz, the path loss over 50 feet is 71.8 dB, and at 7.125 GHz, it's 73.6 dB. Whether that nearly 2 dB matters might be compensated for by a different coding scheme. I've never gone looking for the data on how their systems work. The power limits for safety are the same so they won't transmit with more power.

    2. 1024-QAM is going to need some really decent SNR to work well.
      And I was comparing this to the 2.4 GHz standard that most homes are still working with. Most people don't upgrade their wireless routers all that often. But at least they're not directly competing with the microwave oven.

      I'd love to play with these signals with the gear I used to have access to. Oh, well. Time marches on, and all things change.

  3. I remember listening to a podcast, which I highly recommend, called "The Amp Hour": Chris Gammel and David Jones (of the eeVblog) talk about all sorts of engineering topics. It almost makes up for the rest of the internet :-P.

    On one of their shows they were talking with an engineer from Bell Labs talking about one aspect being lumped under the banner of "5G": Using a higher-frequency part of the microwave spectrum with a lot of available bandwidth. At the end of the episode the hosts (always polite, but you could sort of tell by the tone of their voice) were a little nonplussed at all of the workarounds you would need for it to work. Line-of-sight only transmission, won't penetrate glass, won't penetrate your hand if you were holding a cellphone, gets eaten by the atmosphere over km distances.

    Sounds to me like it'd make more sense as some sort of microwave tower-to-tower trasmitter, than tower to end-user-device.


  4. Also: Heads up:

    Springer has released ~400ish physics/engineering textbooks online for free to download during the coronavirus mess.


  5. Hmm, such tough choices. Should I read Control Engineering: MATLAB Exercises? or Research Methods for Social Justice and Equity in Education with Chapter 1: Re-positioning Power and Re-imagining Reflexivity: Examining Positionality and Building Validity Through Reconstructive Horizon Analysis ?

  6. I dunno, the "Physics from Symmetry" book is kinda meh, but explores some topics I've been interested in. The "Physics of Semiconductor Devices" is ... comprehensive.

    And at least now I know what VHDL actually does internally, which will be helpful during an FPGA project for this phased array thingy...