Research On Delay Optimization Technology Of Wireless Time-sensitive Networks

With the development of Industry 4.0,different types of new industrial applications have been deployed in factories,which puts forward real-time and high-speed requirements for industrial wireless technology.However,the existing industrial wireless transmission technology has been unable to provide dynamically changing bandwidth transmission services and flexible access technologies for new industrial equipment.At the same time,in the current industrial wireless technology,it is impossible to allocate time slot positions according to the data type,which makes it impossible to further optimize the queuing delay.In this thesis,the wireless time sensitive network access mechanism and dynamic time slot allocation technology are studied to optimize the network delay.The access mechanism uses the advantages of Time Division Multiple Access(TDMA)and Carrier Sense Multiple Access with Collision Avoidance(CSMA/CA)to provide dynamic changes for terminal equipment The transmission service with bounded bandwidth and delay is optimized for time slot allocation based on the data types of different terminal devices.The main innovations are as follows:1.Study the time slot allocation algorithm based on delay optimization.According to the different types of data transmitted,establish a data arrival model and a queue length model,and then establish an objective function for minimizing network delay;then in order to calculate a better number and position of time slots allocated by each device,this thesis uses the improved Particle swarm optimization is used to solve the problem.Finally,Matlab simulation is used to compare and compare with other existing algorithms,which proves that the algorithm is feasible and effective.2.Design and implement a Dynamic TDMA System(DTS)based on Software Defined Network(SDN).First,design a wireless access method that mixes TDMA and CSMA/CA.Through feedback and negotiation at the CSMA/CA stage and data transmission mechanism at the TDMA stage,to meet the bounded delay requirements of the devices in the network;then to deploy the hybrid TDMA/CSMA access method,we modify the terminal equipment and wireless access point(AP);finally,a time slot management module is added to the SDN controller to deploy a time slot allocation algorithm based on delay optimization.3.Finally,the DTS is tested in actual network equipment.The results show that compared with other schemes,this thesis proposes that DTS can reduce the queuing delay of data of all equipment,improve the utilization of time slot resources,and thus improve network throughput.