6GHZ Free Space Path Loss

July 20, 2021

François Vergès



We have wrote about Free Space Path Loss on this blog. Take a look at this article to understand what it is: https://semfionetworks.com/blog/free-space-path-loss-diagrams/

In this article, we are going to focus on what Free Space Path Loss will look like on the 6GHz frequency band.

To start with, here is the updated FSPL diagram including the 6GHz loss:


The following table presents the different channels that will be available for Wi-Fi use in the 6GHz frequency band in Canada (click to enlarge):

If you want to take a deeper look at which channels are defined by the IEEE 802.11ax amendment, take a look at this document put together by Josh Schmelzle that details the different 6GHz channels: https://docs.google.com/spreadsheets/d/1C7RxH1R3aRgvO0aeL-b79n6_W5vbcMVynqW9FlDZoLg/edit#gid=1958479420


As a reminder, here is what the Free Space Path Loss formula looks like:

When we calculate the FSPL after 1m on each of the 6GHz channels, we get an average loss of 48.74dB across the entire 6GHz band. Here are the average per sub-bands:

  • UNII-5 Average: 48.29dB
  • UNII-6 Average: 48.70dB
  • UNII-7 Average: 48.99dB
  • UNII-8 Average: 49.23dB

Here is a table the details these results:

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Tom Van Driessche


is your formula correct? Shouldn’t it be 32,45 in stead of 92,45?



Great article! I was concerned about how much loss to expect from 6GHz vs what we have with 5GHz and it looks pretty minimal! Thanks for the thorough explanation and great diagrams!

David Coleman

Good blog…. I have similar slides that I am using internally to discuss the whole 1st meter concept for FSPL in regard to 5 GHz versus 6 GHz