Research On Modeling And Analysis Of Internet Of Vehicles Communication Based On Stochastic Geometry

With the rapid development of intelligent transportation system in the past decade,the Internet of vehicles（Io Vs）technology has become a research hotspot in the field of intelligent transportation.The arrival of the fifth generation mobile communication technology（5G）has greatly promoted the development of Io Vs.At present,there are two main communication protocols in the Io Vs: the 802.11p/WAVE protocol and the LTE-V protocol（which is raised by China Communications）.However,these two protocols have their own limitations in practice.Therefore,a cooperative network combining them protocols will provide a feasible solution.Fortunately,the software defined network（SDN）adopted by 5G networks provides a positive support to the realization of V2 I communications over 5G-802.11 p collaborative networks.Based on the shortcomings of the existing geometric distribution model of the Internet of vehicles,this paper first proposes a more reasonable model by using the Poisson Point Process（PPP）and Poisson Line Process（PLP）in stochastic geometry and according to the proposed model and the existing networking scheme,the relationship between the coverage probability and the number of vehicles,base stations（BS）and roadside units（RSUs）in 5G-802.11 p cooperative network scenario is derived.Then,the existing networking scheme is improved,and a more practical networking scheme is proposed.The mathematical expression of coverage under the new networking scheme is derived,and the correctness of the theoretical results is verified by simulation experiments.Finally,the theory is applied to practice: Taking Ganjingzi District of Dalian City as an example,this paper discusses the number of RSUs that need to be built to reach the ideal coverage based on the existing BSs under the 5G-802.11 p cooperative network scenario.Main contributions of this paper are summarized as follows:（1）Based on the distribution characteristics of vehicles and roadside units,we propose a more reasonable geometric distribution model for the Io V scenario and derive the expression of coverage based on the proposed model.Existing geometric models only consider the randomness of the distribution of vehicles and roadside units,but ignore the characteristics of the distribution of roadside units and vehicles along the road.In order to better describe this feature,we first capture the road structure,that is,the Poisson Line Process is used to model the road distribution.Then the vehicles and roadside units are limited to be located on the road,and the geometric distribution models are established by using the independent onedimensional Poisson Point Process.（2）It is known that the number of vehicles that a single roadside unit can serve simultaneously cannot be set as infinity in practice as that of theoretical assumption.When the vehicle density is too high,the roadside unit will reach a saturation state.Therefore,we introduce the maximum number of vehicles that can be served by a single roadside unit simultaneously in the derivation of coverage probability.We also compare the coverage probability of the practical case with that of the ideal case（i.e.the number of vehicles served by one RSU is set as infinity）.