Abstract: In order to reveal the dynamic topological characteristics of Vehicular Ad-hoc Network (VANET), predict the behavior of VANET and alleviate the traffic congestion, extensive simulations of information propagation under normal circumstances from the microscopic point of view, we investigate the information flow distribution characteristics of VANET and the relationship between its information flow and degree of the node under different traffic demands in VANET. Firstly, the relationships among the degree, the degree distribution index and the information flow are proposed, and then scale-free network model is established with static and dynamic methods based on complex network theory, and when the parameters are varied, the change law of information flow is discussed by numerical simulation. Furthermore, the characteristics of information flow in capacity constraints are studied by means of nonlinear dynamics theory. Numerical results show that the information flow index is a general characteristic parameter of the scale-free network, and those larger degree nodes have a greater effect on the network and which also have faster propagation speed. We also find that the relationship of information flow and nodes degree obeys the power law distribution. Hub nodes may be overburdened when the information flow demand increases, and many information flows may choose other nodes to avoid communicating with the Hubs nodes, then the smaller degree of nodes will undertake this part of the information flow.

Key words: intelligent transportation, information flow characteristics, power-law distribution, complex network, VANET