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Contributions to the ITU

Starting in 2014, numerous measurement campaigns to collect directional channel propagation data in both indoor and outdoor environments, through our switched-array channel sounders at 28, 60, and 83 GHz bands, were conducted. The data were recently compiled as proposed revisions to supplement existing parameters in ITU Recommendations P.1238-10 (indoor) and  P.1411-10 (outdoor) – for pathloss, RMS delay spread, and RMS angular spread models. In all, NIST contributed a total of 16 sets of model parameters collected from a total of nearly 7000 unique receiver positions. Our indoor pathloss data were accepted as a part of a new section “Site-general models” in P.1238-11 document [1], while our outdoor data contribution is under “Working items for future revision of Rec. P.1411-11” [2].

In 2019, we conducted an extensive measurement campaign on our NIST campus in Gaithersburg on propagation through trees. Statistics on the channel model parameters of attenuation through vegetation and the resultant scattered angle-of-arrival, were reduced from the measurements and proposed for inclusion in Recommendation ITU-R P.833-9 "Attenuation in vegetation". After several stages of review, our contribution received final acceptance into the recommendation under new section titled "Seasonal effects on single trees at 60.5 GHz" [3].


Attenuation through the same tree in summer and winter at 60.5 GHz. Attenuation through rich vegetation during summer (lines with no symbols) is higher comparing with attenuation during winter (lines with symbols) as a result of the leaves withering. 


More details about our ITU contributions can be found in the references below:

[1] “Propagation data and prediction methods for the planning of indoor radiocommunication systems and radio local area networks in the frequency range 300 MHz to 450 GHz,” International Telecommunication Union, Recommendation ITU-R P.1238-11, Section 3.1 "Site-general models", Sept. 2021.

[2] "Propagation data and prediction methods for the planning of short-range outdoor radiocommunication systems and radio local area networks in the frequency range 300 MHz to 100 GHz," International Telecommunication Union, Recommendation ITU-R P.1411-11, Sept. 2021.

[3] “Attenuation in vegetation,” International Telecommunication Union, Recommendation ITU-R P.833-10, Section 3.2.3 "Seasonal effects on single trees at 60.5 GHz", Sept. 2021. 


Radio Access and Propagation Metrology Group

Created September 28, 2021, Updated November 1, 2021