Research On Telecommunication System EMC Assessment By Fuzzy Comprehensive Method

For limited space communications system platforms,many equipment which working frequency very close are installed to perform different functions,the surrounding electromagnetic environment also has become increasingly complex,these bring about the adverse effects between different equipment and also cause serious electromagnetic compatibility(EMC)problems.Therefore,master communication system EMC is the premise and foundation of communication equipment platform system management and maintenance,at the same time,it has became a hot research in related field.Get communications system platform EMC data through experimental is a conventional and effective technical method,but this need long period and the process is also complicated,with the development of system simulation technology,EMC simulation and predictive analysis to assess the communication system based on the experimental test data,this will be another effective solution to solving the above problem.In this paper,take the most technologically sophisticated communication system as an example to research,the communication system electromagnetic compatibility assessment is achieved based on equipment performance curve.This assessment methods is universal and can be used to other system EMC assessment.Firstly,through analyzing the scope of the traditional assessment methods,determining to select Fuzzy comprehensive evaluation method as communication system EMC assessment model,due to the weights has strong subjectivity and membership functions to determine is also difficulty,For it's deficiencies,improvements is proposed between the weights and the membership functions to improve the accuracy of the assessment results.Next,through study of the interference between equipments and signal processing in sensitive equipment receiver,sort out the different factors that affect communication systems EMC,communication system EMC evaluation index is established.At the same time,computing and simulating the changes of the equipment performance with different surroundings interference and the law of the interference impact indicators is summarized,this laid the foundation for the subsequent assessment model.Then according to the equipment performance curve changes with the interference andcombine with the requirements of system equipment in relevant standards,the communication system EMC assessment levels is defined and proposing the interval range calculation method of different levels,the initial evaluation index framework is established.In order to improve the accuracy of the assessment,confidence analysis is introduced into the evaluation process to analysis and verify the accuracy of the weight coefficients,and proposing detailed calculation steps based on the curve of equipment to solve the membership function.Taking the BER as an example,obtained corresponding to different assessment levels of membership function by numerical simulation.Finally,through taking an example to verify the proposed communication system EMC assessment theory and methods,establishing the communication system EMC evaluation index hierarchy,combine voice equipment in analog communication systems and digital equipment in digital communication systems,according to the assessment model combining membership function and weight values,completing the whole assessment process successfully.