Research On Risk Assessment Of Railway Mobile Communication System Based On Set Pair Analysis

LTE(Long Term Evolution)technology has been used for a long time in public mobile communication networks and has the maturity and stability to be used as a conventional technology for railway mobile communication.Considering the safety requirements of LTE-R(Long Term Evolution for Railway)communication system,it is important to study a set of scientific and practical risk assessment scheme for LTE-R communication system to provide reference for the development,improvement and evaluation of LTE-R system,so as to ensure the safe service and operation of LTE-R system.It is important to ensure the safe service and operation of the LTE-R system.This thesis takes LTE-R communication system as the research object,based on the existing literature on the security of railway wireless communication system,and proposes a risk assessment method for railway LTE-R communication system based on SPA(Set Pair Analysis)to identify system security problems in time to prevent security incidents,in view of the problem that there is not much research on the security analysis of high-speed railway LTE-R communication system network structure and operation and maintenance management.The thesis firstly introduces the system architecture of LTE-R communication system,bearing services and key technical advantages,and then explains the risk,risk matrix and risk assessment theory.Based on the theory of system safety engineering,a large amount of relevant literature is comprehensively referred to from the five major aspects of LTE-R communication system safety identification from business,equipment,network,management and maintenance that affect system safety,combined with the principles of the construction of assessment index system,LTE-R communication system system risk assessment system is established,and the assessment index is quantified and analysed.Secondly,combining with the five-element linkage number structure in the set-pair analysis theory,the risk of LTE-R communication system is divided into five risk levels,a posteriori weight calculation method based on interval unambiguous judgment information is constructed,the weight intervals are calculated using IAHP(Interval Analytic Hierarchy Process),and then the weights are calculated as exact values using the ternary in SPA The weights are then computed to exact values using the ternary linkages in SPA.By combining the probability of risk occurrence and the weight,a risk assessment method based on SPA is proposed for LTE-R communication system,which is used to analyse the risk posture and risk change trend of LTE-R communication system.Case verification shows that the security level of the system is low risk,which is in line with the actual situation in the field.Finally,according to the LTE-R communication system risk not only has uncertainty but also dynamic characteristics,the SPA-Markov Chain-based coupled LTE-R communication system risk assessment model is constructed by introducing Markov Chain to optimize the set-pair analysis method.Among them,the risk level at different moments is expressed using the mathematical expression of the degree of connection,and the LTE-R system risk level state probability matrix is used to analyze the risk development trend of the whole LTE-R system and predict the future risk state of the LTE-R system.Finally,the risk change trend of LTE-R system is analyzed by example,and the steady-state risk prediction of the next January and LTE-R system,which proves that the model is practical and feasible and provides a theoretical basis for the safety management of LTE-R system.