Degradation of transmission range in three-dimensional scenarios of VANETs

In vehicular ad hoc networks (VANETs), three-dimensional scenarios are always ignored, even though they are attractive for their effectiveness in land use. Focusing on those scenarios, we propose and prove their severe impacts on the performance of a vehicular network. We first conduct a transmission experiment. The results prove that the existence of those scenarios induces the inter-layer communication, and then significantly reduces the transmission range. Furthermore, we demonstrate that the variation of the transmission range makes an enormous difference in the neighbor number, which severely affects the network performance. At last, our extensive simulations show that the aforementioned analysis are in fact quite accurate.