Research On Parallel Optimization Of Real-time Message Scheduling In Wireless CPS Based On Event Driven

Cyber-Physical Systems is a multidimensional and complex system,integrated of computing?network and physical environment.It has great application prospect in traffic,defense,energy,medical and large-scale buildings.Real-time service quality is an important factor restricting its development.In Cyber-Physical Systems,the mechanism and strategy of message scheduling determine the quality of its real-time service quality,and the parallel optimization of message scheduling is an important link in the design of message scheduling mechanism and strategy process.Reasonable parallel optimization method of message scheduling can not only avoid or reduce channel competition and collision conflict,but also increase the stability and reliability of message scheduling process,improve resource utilization and prolong system life.In this thesis,the National Natural Science Foundation of China is used as the source,and it focuses on the parallel optimization of real-time message scheduling.This thesis analyzes the characteristics of wireless network event message and the factors that affect the utilization rate of wireless network channel.It classifies the wireless network message scheduling method,which is mainly based on the competition method,based on time division multiplexing method,the hybrid method,based on the priority method,etc.Through in-depth analysis,we can see that the message scheduling method based on time division multiple access is more in conformance with the characteristics of Cyber-Physical Systems.Starting from the parallel optimization of message scheduling and time division multiplexing theory,the thesis proposed a event-driven real-time message parallel scheduling algorithm(ERMPSA).The algorithm started from three aspects,which includes the judgment of parallel message,the message transmission path and the message parallel transmission.It takes meeting the deadline of message as the primary target.And then it also considers the residual energy of the node and the average delay of the network.In order to keep as many messages as possible in parallel,the parallel optimization model based on message scheduling establishes the corresponding message graph for the messages to be transmitted in the same slot.Coloring theory are applied to maximize the parallel transmission of messages.The result of experiment shows that the parallel optimization model and ERMPSAalgorithm of message scheduling can effectively improve the parallelism of the message transmission process.Compared to existing message scheduling method,ERMPSA can significantly reduce the message deadline loss rate without increasing the energy consumption of the node,and also reduce the average delay and improve throughput of the network.