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@ -81,10 +81,10 @@ See in the references of the above LoRa world record transmission distance detai
For a bit of light reading on environmental research:
- [RF attentuation in vegetation](https://www.itu.int/dms_pubrec/itu-r/rec/p/R-REC-P.833-9-201609-I!!PDF-E.pdf) (yes really) ; if you wander through the woods wondering how your RF is bouncing off leaves dependent on their variety, and wind speed … well I do, now.
- [RF attentuation in vegetation](https://www.itu.int/dms_pubrec/itu-r/rec/p/R-REC-P.833-9-201609-I!!PDF-E.pdf) (yes really); if you wander through the woods wondering how your RF is bouncing off leaves dependent on their variety, and wind speed … well you do, now.
- [RF attentuation with various building materials](https://www.ofcom.org.uk/__data/assets/pdf_file/0016/84022/building_materials_and_propagation.pdf).
- This one by ITU again is very detailed in its analysis of the drivers of attenuation; rather than the article above (Ofcom) which simply measures … https://www.itu.int/dms_pubrec/itu-r/rec/p/R-REC-P.2040-1-201507-I!!PDF-E.pdf (I wasn’t aware that all EMF radiation exhibits reflection / transmission characteristics akin to light hitting a material boundary. So, depending on the angle of incidence, material and the EMF wavelength, it will be reflected and / or transmitted through).
- These RF bands are also made more noisy by adjacent LTE https://www.ofcom.org.uk/__data/assets/pdf_file/0023/55922/lte-coexistence.pdf
- This one by ITU again is very detailed in its [analysis of the drivers of attenuation](https://www.itu.int/dms_pubrec/itu-r/rec/p/R-REC-P.2040-1-201507-I!!PDF-E.pdf) (I wasn’t aware that all EMF radiation exhibits reflection / transmission characteristics akin to light hitting a material boundary. So, depending on the angle of incidence, material and the EMF wavelength, it will be reflected and / or transmitted through).
- These RF bands are also made more [noisy by adjacent LTE](https://www.ofcom.org.uk/__data/assets/pdf_file/0023/55922/lte-coexistence.pdf)
In summary - our wavelengths in Europe fair well in plain sight, curve over not-so-tall obstacles (including trees), reflect of surfaces at low angles of incidence. They go through humans without much attenuation; but not brick or stone or anything much above glass / kevlar. Oh, and don’t sit under an LTE tower and expect it to be plain sailing.