SEMIEMPIRICAL MODEL FOR MILLIMETER-WAVE VEGETATION ATTENUATION RATES

An improved empirical model of the attenuation rates due to propagation through vegetation at millimetre-wave frequencies is described. The measured vegetation attenuation rates of 38GHz signals were fitted to a two-parameter model with a final slope of OdB/m, to give an improvement in fit over the current ITU recommendation. However, this final slope is not a typical characteristic and is not seen at other frequencies. A new three-parameter model has been developed, which may have a nonzero final slope, giving the model greater freedom and therefore a better fit to measured data at ail frequencies.