A Demand-Aware Multichannel Coordination MAC Protocol Design Based On Queue Model In VANET

With the continuous economic development in our country,people's demand for transportation resources has become more and more.However,the vehicle's high mobility and dynamic network topology on the highway have brought great trouble to the network connectivity.Therefore,how to design a connectivity model to improve the connectivity in vehicular communication networks and to design a medium access control(MAC)protocol based on this connectivity model is a hot research topic.This paper mainly studies the connectivity of queue model and MAC protocol design based on queue model vehicle ad hoc networks on the highway.The main research contents are as follows:Firstly,the transmission of data packets must be based on the environment of network connectivity.In order to ensure that the vehicles can access the network under any circumstances on the road,this paper presents a connectivity model based on Queue Model.The model mainly analyzes the relationship between the parameters such as base station spacing,vehicle travel speed,adjacent vehicle spacing,adjacent queue spacing,base station coverage,common vehicle nodes,coverage and connectivity probabilities under single-lane and multi-lane conditions.And given the queue ratio and connectivity probability,the adjacent base station deployment spacing can be calculated.The simulation results show that the performance of connectivity in queuing model is obviously better than that in the absence of this model.The result of this study provides a guarantee for MAC protocol in vehicular ad hoc networks.Secondly,based on the queue connectivity model,this paper proposes a demand-aware MAC protocol with multi-channel priority control.This protocol reserves the control channel by periodically broadcasting the data packet by the base station,and can dynamically change the time slot according to the traffic information and the connectivity probability in real time,then using the multi-level priority Markov chain to realize the priority control.Simulation results show that the MAC protocol proposed in this paper has obvious performance improvement compared with WAVE MAC and VCI MAC in channel throughput and end-to-end delay.