Intellisense And Access In Rail Traffic Wireless Communication Scenario

With the rapid development of economy and society,people's requirements for information and intelligence of rail traffic are increasing.Now,the research on the intellisense of passengers' movement and location information and security access control in the rail traffic wireless communication scenario has been widely concerned.As intelligent transportation is an important part of smart city,the realization of intellisense and efficient processing of rail traffic information can help to alleviate the traffic congestion in modern cities and is useful for smart city construction.At the same time,the design of security access control mechanism of rail traffic wireless network can resist the interference as well as damage of attackers effectively,and can improve the security of train operation.In view of the above requirements,based on the measurement data,this thesis designs and completes the intellisense and access in the wireless communication scenario of rail traffic to serve intelligent transportation.The specific work and contributions of this thesis are as follows:Firstly,this thesis selects the real rail traffic communication scenario in Beijing Railway Administration and configures the measurement equipment.Then,the Received Signal Strength(RSS)and Channel State Information(CSI)in the 5.805 GHz frequency band are collected.Based on the measurement parameters of the train,this thesis builds and refines the rail traffic scenario model with Sketch Up software.Then,a location sensing algorithm based on trajectory analysis at the time when the train stops at the platform is designed.Based on the RSS and CSI data collected during the measurement,this thesis completes RSS trajectory simulation and data filtering.Then,to extract the unique movement pattern of passengers when they enter or leave the train coach from the door of it,Dynamic Time Warping(DTW)is used.Not only can it judge the physical area where passengers are located,but also it can complete intelligent traindeployed Wi-Fi access in the rail traffic scenario.A typical application of that is to enable real-time monitoring of passenger flow,thereby providing data for the construction of train dispatching and emergency management systems during busy time.Finally,in order to ensure the security of Internet of things terminal equipment in the train,a security access model based on location sensing is designed.Considering the demand to determine the terminals' location in the system,the security access algorithm based on neural network localization and the security access algorithm combined with Ray Tracing(RT)localization are proposed respectively.The input data set of the former is constructed by the measurement data,and the network training is completed by using the back propagation algorithm.And the localization of the terminal equipment trying to access the train-deployed Access Point(AP)is realized.Combined with the proposed access model,the high accuracy security access algorithm based on neural network is realized.The latter combines the Three-Dimensional(3D)model of the scenario and uses RT simulator to complete the simulation.The Multiple Input Multiple Output(MIMO)channel information obtained from simulation is extracted to build the input data set,and neural network is used to complete the localization of intelligent equipment.Finally,a lightweight security access algorithm is realized to ensure the security of wireless network.