Research On Layout Optimization Of Hybrid VANET-Sensor Networks For Autonomous Driving

In recent years,vehicles on the road have continued to increase and continued to grow,and autonomous vehicles have begun to rise.How to improve the driving safety of autonomous driving and enhance the real-time performance of the intelligent transportation communication system has become a hot issue of social concern.Since the autonomous vehicles need to obtain local and global road conditions for safe driving on the road,it is very important to establish a complete information transfer architecture model with the assistance of the roadside infrastructure.However,the traditional Vehicular Ad-Hoc Network(VANET)lacks real-time monitoring of road conditions and the transmission delay in 4G network is insufficient to meet the operation of the VANET network.This thesis proposes a method of integrating the VANET and the Wireless Sensor Network(WSN).By jointly deploying the Road Side Units(RSUs)and the sensors on both sides of the road,the RSU communicates with the 5G micro base station to transmit information to the edge-cloud data center.Then the road conditions are monitored and the vehicles on the road are fully covered,so that the vehicle can directly communicate with the roadside equipment through one hop to improve the real-time performance of the road information and reduce the delay of network transmission.This thesis designs a new network architecture model of Hybrid VANET-Sensor Network(HVSN),and solves the network Layout Optimization Problem(LOP)in HVSN,then obtains the optimal network layout planning under the premise of minimum deployment cost.Firstly,according to the characteristics of the Hybrid VANET-Sensor Network(HVSN),a tree-based structure on this hybrid network is designed.This tree-based structure is suitable for road monitoring and deployment in urban environments,and the tree-based structure is easy to extend and has high fault tolerance.In order to avoid wasting resources during deployment,the number of network element devices deployed in the urban environment should be reduced.Therefore,the optimization objective of the HVSN network layout optimization is to minimize the network deployment cost.Secondly,taking the urban road as the application scenario,deploying the RSUs and the sensors on both sides of the road and selecting the appropriate micro base station in the HVSN network,adopting the V2I communication mode and ensuring the counectivity between the network element devices in the network is an NP-hard problem.Therefore,this paper establishes a mathematical model for Layout Optimization Problem(LOP),considers the constraints of transmission distance and network capacity,establishes an Integer Linear Programming(ILP)model,and uses Gurobi to solve the model,obtains the layout optimization results of the network,and verifies correctness and feasibility of the LOP mathematical model.Finally,the large-scale scenarios those use Gurobi solver have a long solution time and low efficiency,a heuristic algorithm is proposed.The heuristic algorithm can obtain a sub-optimal solution for network deployment and has higher efficiency.Through many simulation experiments,the experimental results of ILP model solving and algorithm solving are compared and analyzed.The simulation results show that the proposed algorithm has high efficiency and scalability.This thesis optimizes the deployment of the HVSN,reduces the network cost and transmission delay,enhances the real-time performance of road information transmission,makes the network more economical and reliable,and provides the theoretical basis and technical support for actual deployment of the HVSN network.