Measurements and modelling of wind influence on radiowave propagation through vegetation

Movement of vegetation structures introduces an adverse environment for high frequency radiowave propagation. This paper examines a series of vegetation scattering measurement campaigns during various wind conditions. The measurements were divided into controlled and outdoor environments. The controlled environment measurements were conducted in an anechoic chamber at 0.9, 2, 12 and 17 GHz. The outdoor measurements were carried out at 1.8 GHz and involved in recording of a transmitted signal originating from an existing digital cellular system (DCS-1800) base station. The obtained results are discussed and presented in terms of their first- and second-order statistics. Analysis demonstrates that the received signal behaviour is highly wind dependent, especially when the environment is changing from calm to a windy condition. The signal fast-fading is found to be Rician distributed and an empirical model of the k-factor variation over wind speed is also presented.