Research On Wireless Resource Scheduling Technology In Internet Of Vehicles

With the rapid development of the vehicle manufacturing industry and the information and communication industry,the Internet of Vehicles(Io V)technology,an emerging product of the integration of the two industries,has gradually entered people’s lives.It plays an important role in preventing traffic accidents,improving traffic efficiency,and improving driving experience.In terms of the way in which the vehicle networking communication system acquires wireless transmission resources,the way that vehicles autonomously select transmission resources has gradually become the main method of resource acquisition due to the characteristics of not being restricted by the location of the base station,and is also the current focus of research on the V2 X.However,the V2 X system has drawbacks such as selection conflicts when it autonomously perceives and selects resources,and does not classify and process services with different priorities.Therefore,in terms of reducing conflicts in vehicle resource selection and ensuring the service quality,it is necessary to make improvements for the current V2 X resource selection and scheduling schemes.In response to the above-mentioned problems,the main research work carried out in this thesis and the main results obtained are as follows:Firstly,the related concepts of the V2 X system are summarized,the current domestic and international standards for the V2 X are briefly introduced,and the key technologies used in resource selection and scheduling of the existing V2 X framework are described.The V2 X communication scenarios,service requirements and transmission resources in the NR-V2 X standard are introduced,and the Semi-Persistent Scheduling SPS used in resource selection scheme is analyzed.It is pointed out that this scheme has problems in avoiding resource conflicts and guaranteeing quality of service,which need to be improved and optimized.Secondly,regarding to the problem of classification guarantee for different services,a scheduling scheme of resource selection based on quality of the service in the V2 X is proposed.The scheme fully considers the small tolerance of delay and packet loss rate when vehicles send security services.When the load is heavy,multiple services are sent at the same time,and multiple resource blocks are selected according to the different constraints of the services on resources,so as to improve the probability of successful transmission.When the scheme is implemented,the number of services scheduled in a single time and the number of resource blocks occupied by data packets are optimized according to the number of services in the service buffer queue,the priority of the services,and the maximum tolerable packet loss rate.Afterwards,the performance of the scheme was analyzed and simulation verification was carried out.It can be concluded that the proposed scheme has a significant improvement in the data packet reception probability and the transmission success rate of high-priority services compared with the traditional Semi-Persistent Scheduling scheme.Finally,with respect to the transmission reliability of high-priority security services,a resource pre-emption scheme based on service priority in the V2 X is proposed.This scheme is based on the the resource block pre-emption and re-evaluation mechanism proposed by the latest NR-V2 X protocol standard,when transmission resources are in short supply,the resource blocks reserved periodically by low-priority services are pre-empted to achieve the goal of service quality assurance for high-priority services.When the scheme is implemented,it is determined whether to pre-empt based on the resource occupancy rate and the average service priority,and the pre-emptible resource blocks are selected based on the priority value and the remaining period value of each resource block.After the simulation verification of the proposed scheme,it can be concluded that the proposed scheme has a significant improvement over the traditional Semi-Persistent Scheduling scheme in terms of packet reception probability and high-priority service transmission success rate.