Measurements and prediction model optimisation for signal attenuation in vegetation media at centimetre wave frequencies

The effects of vegetation media on the planning and design of radio links at microwave and millimetre wave frequencies are considerable and must be accounted for by radio system operators and users. The paper presents propagation models for the excess attenuation of signals caused by such media whose mathematical descriptions have been optimised using measured data obtained at three sites. The paper shows that one of the models which expresses the attenuation as a function of frequency and depth of vegetation gives close predictions for the two broad generic cases of trees “in-leaf” and “out-of-leaf” and can be recommended for use in the range 10-40 GHz