6G Channel Characterization


I think the way we investigate on channel characterization would be similar regardless of the frequency range. So if you have any knowledge on channel characterization for any of previous technology (e.g, 5G channel characterization), it would be much easier to follow up on Terahertz Channel Characterization. If you are interested in my note about 5G channel characterized done in before and early 5G standization, check this page.

As of initial writing of this note (May 2021), I haven't got much of the information about 300Ghz ~ 1 Thz yet. Most of the information (e.g, tech articles or papers) on this topic is largely around D-Band (110~170 Ghz) or W-Band(75~110Ghz).

: In early 2021, some papers and white papers are published on channel sounder in 300 Ghz region, but with distance between Transmitter and Reciever is just around a few meters. (Check here )




Atmospheric Attenuation


This is about Atmospheric Attenuation. As commonly understood, we see the general tendency of increasing attenuation as frequency goes higher. As a result, we will see higher attenuation in Tera Hertz candate (C) frequency comparing to 5G or D band (B). In the 6G Candidate ranges, we see much less attenuation in dry environment ((1) & (2)) comparing to standard environment ((3) & (4)) implying that interacting with water molecule would play an important role. The attenuation at higher altitude ((1) & (3)) is lower than the case at sea level ((2) & (4)).



Source : NYT Wireless - Publication




Attenuation by Rain


In terms of Attenuation by Rain, it is obvious that the precipitation affects a lot on attenuation, but regarding the frequency effects there is not much differences between 5G FR2(C) and 6G Candiate Frequency(D, E).



Source : NYT Wireless - Publication




Path Loss Model






Source : NYT Wireless - Publication




Attenuation by Foliage


Source : NYT Wireless - Publication



Source : NYT Wireless - Publication




Channel Sounding



Example : THz Channel Sounding: Design and Validation of a High Performance Channel Sounder at 300 GHz











Example : Channel Sounding Techniques for Applications in THz Communications