How is the 60GHz spectrum affected by oxygen?

Both rain and oxygen can heavily impact signal levels in the 60GHz band.  

Oxygen absorbs the signal in the lower half of the light licensed 60GHz band with a peak at channels 2 and 3 of around 15dB/km at sea level.  

This amount varies based on altitude since altitude also has an impact on the amount of oxygen in the path.  

Channel 1 is less impacted by oxygen absorption at around 12dB/km and channels 5 and 6 are minimally impacted by oxygen absorption as shown in the graph below:


Channel planning

These physical characteristics can be very useful when planning deployments:

  • For high densities of shorter links using the channels with high oxygen absorption results in less self-interference and a higher amount of channel reuse since the oxygen is eliminating the signal quickly past the usable range.

  • For longer links, the upper channels enable longer connections.

Summary: the 60 GHz upper band channels are less affected by oxygen absorption than the lower channels.