Measurement and Characterization of Vehicle-to-Vehicle Channels in Vegetated Environment

The characterization and modeling of wireless channels are crucial prerequisites for designing and deploying communication systems, which have been widely recognized. It must be measured and investigated, especially for vehicle-to-vehicle (V2V) channels, because it differs from the general cellular network in propagation environment, transceiver height, and communication frequency. Vegetation in the road environment is expected to block the propagation signal and have an uncertain impact on channels. Therefore, the loss of communication quality due to vegetation can not be ignored for safety-related applications. This paper measures V2V channels in a vegetated environment, emphasizing the changes in large-scale fading, power delay features, spatial stationarity, and multipath characteristics caused by vegetation obstruction. Specifically, this paper points out that vegetation obstruction makes the wireless system need about 8 dB of extra fading margin and causes the average delay spread to increase by 30 ns. At the same time, vegetation obstruction intensifies the non-stationarity of V2V channels, resulting in a smaller stationary distance. In addition, in terms of multipath spatial characteristics, the azimuth spread has increased to about two times that of the general line-of-sight (LoS) scenario, which means more significant spatial dispersion. In this paper, the influence of vegetation obstruction on channel key parameters is quantified and modeled comprehensively. It is helpful to deepen the excavation of V2V channel propagation mechanisms and assist the revision and evolution of the existing general channel model.