Research On Intelligent Resource Scheduling Strategy Of IoV Based On 5G NR Technology

V2X is the most important technology in Internet of vehicles（Io V）.A reasonable resource scheduling strategy can effectively improve the performance of V2 X network to meet the requirements of intelligence and security.This requires not only the real-time resource scheduling to meet the complex and rapidly changing scenarios of Io V,but also the differentiated quality of service（QoS）requirements of a variety of different services existing simultaneously in Io V.Based on the background above,this thesis proposes two intelligent resource scheduling strategies for Io V based on 5G New Radio（5G NR）technology.There are many services with different requirements coexisting in Io V.On the one hand,5G network usually reserves a certain amount of resources for high priority ultra reliable low latency communication（URLLC）services in the form of slicing to ensure reliability.However,the fixed slicing strategy will lead to low resource efficiency and affect the performance of other services.On the other hand,5G NR supports the scheduling of resources in different time scales to adapt to multiple applications.The high subcarrier spacing（SCS）configuration can meet the low delay requirements of URLLC services,but it will lead to user access constraints,and the low SCS configuration is difficult to ensure the reliability of URLLC services.To solve the problems above,this thesis proposes a preemptive resource allocation algorithm based on 5G NR mini-slot scheduling technology.The resource is pre-allocated with the time slot as the cycle to ensure the efficient transmission of large traffic services.The location of preemptive resources is selected when the key services arrive with the time scale of mini-slot,and the service priority composed of traffic,delay demand and vehicle stay time in the cell is considered,To ensure the reliable transmission of different services.The results show that the mini-slot scheduling algorithm proposed in this thesis can improve the QoS of low priority（e MBB）services under the constraint of ensuring the QoS of high priority（URLLC）services.In Io V,the proportion of uplink and downlink traffic from vehicle to infrastructure（V2I）and transmission traffic from vehicle to vehicle（V2V）changes dynamically.The traditional cellular network adopts static slot matching or pre-defined mode,which cannot meet the dynamic requirements in the scenario of Io V.With the support of 5G NR,each part of the time slot can be used for uplink,downlink or flexible slots to dynamically adapt to the needs of different services.However,dynamic scheduling will bring additional control consumption.This paper proposes a two-step dynamic slot scheduling strategy to achieve the trade-off between performance and consumption.In the first level,the base station pre-allocates uplink and downlink slots according to historical service statistical data traffic and current requirements,and reserves a certain proportion of flexible slots.The second scheduler will do the resource scheduling in the reserved flexible slots to dynamically allocate time-frequency resources for V2 I and V2 V users.The proportion of reserved time slots in the first level and the resource allocation in the second level are jointly optimized to achieve the trade-off between dynamic scheduling performance and control consumption.The simulation results show that the two-step dynamic slot scheduling strategy can significantly reduce the control consumption under the condition of ensuring the service QoS compared with the traditional algorithm.