Vehicle-to-Vehicle Wideband Wireless Channel Modeling In Intelligent Transportation System

With the accelerating pace of life and increasing number of vechicles on the roads and tracks, congestion on the road and traffic accidents frequently occurring urgingly need solving. Internet of vehicles in the intelligent transportation systems connect the vehicles on the roads and tracks, respectively, and thus makes each vehicle maintain a database of vehcle-movement state in certain communication range. The vehicle can immediately compute the distance between each other to avoid accidents. Also, internet of vehicles can contribute to selection of optimal route to alleviate the congestion on the road. Thus, internet of vehicles provides solution to modern intelligent transportation systems, which is basically based on the effective and reliable vehicular wireless communication system. As known to us, wireless channel modeling is crutial to design of wireless communication system. So it is indispensable for us to deeply and thoroughly study the vehicular radio channel characterization.The overall structure of this paper is that we divide the vehicle-to-vehicle communication into two parts, i.e. car-to-car communication and train-to-train communication. Considering characterizatics of vehicle-to-vehicle communication including high-speed, high Doppler frequency shift, and low antenna-height, this paper presents channel modeling theory and approach for vehicle-to-vehicle communication, studys large-scale path loss and shadow loss, and small-scale root-mean square-delay spread, tapped-dealy line model, Ricean K factor and multipath envelope correlation. In order to highlight the multipath birth-and-death in the vehicle-to-vehicle channel modeling, we improve the equation of the channel impulse response. We propose relevant probability distributions for the vehicle-to-vehicle channel modeling. We also demonstrate the similarity and difference of modified non-geometrical stochastic and two-dimension geometry-based stochastic channel modeling approaches in the vehicle-to-vehicle channel modeling.By adding height to the transmitter, receiver, static scatterers and diffuse scatterers, we first extend the two-dimension model to thee-dimenstion space.Secondly, motivated by the radio propagation environment, we construct four-level channel architecture for the car-to-car channel modeling. Car line-of-sight propagation, car non-of-sight propagation, car partial non-of-sight propagation (slope and overpass) and car parking-garage environment are seleted for car-to-car wideband channel modeling to explore the influence of extent of the occurring of line-of-sight to the channel characterization. We also use the geometry-based stochastic modeling approach to build simulation platform of slope and overpass scenario. In this platform, from the height dimension, we first consider diffraction in the geometry-based stochastic channel modeling approach.Finnaly, this paper builds the four-level channel architecture for the high-speed train-to-train channel modeling. In order to solve the problem of communication between trains on the same track10km apart, we develop a train-to-train communication model in physical layer using relay of mobile train on the neighboring track for cooperative communication, and deduce the analytical expression of bit-error rate and interrupt probability. We point out that the binary characterization of scatterers around tracks of the high-speed railway in the urban overpass scenario, and illustrate the waveguide effect of radio propagation in this area. Based on this finding, we study the train-to-train wireless wideband channel characterization using geometry-based stochastic channel modeling approach in the aspect of path loss, root-mean square delay spread, tapped-delay line model and Ricean K factor.