Uncertainty Analysis Of Electromagnetic Radiation From Mobile Phones To Human Head

With the rapid development of mobile communication technology in the new era,mobile phones have become a necessary communication tool in people’s daily life.How radiation affects human health has become a topic of much concern.In order to measure the value of electromagnetic radiation received by the human head,people use the index of specific absorption rate to calculate the electromagnetic power absorbed by human tissue per unit mass,so as to evaluate the impact of electromagnetic radiation on health.In the actual test of specific absorption rate In the process,high time cost and economic cost are required.Therefore,it is a necessary solution to use computer simulation to simulate the electromagnetic radiation of mobile phones to the human head.However,the results of traditional electromagnetic radiation simulation calculations are due to the Uncertainty of parameters is prone to errors,therefore,the quantification of the uncertainty of the electromagnetic radiation of the mobile phone to the human head has become an urgent problem to be solved.This thesis focuses on the research on the situation and uncertainty of the electromagnetic model of the human head when it is subjected to electromagnetic radiation from mobile phones,and mainly completes the following tasks:1.First,establish the electromagnetic simulation model of the mobile phone antenna according to the basic theory of the antenna.Through the analysis of the simulation results,the return loss parameters of the antenna in different frequency bands are obtained,and the frequency range covered by the antenna is obtained.Combining the physical model of the block mobile phone and the electromagnetic simulation model of the human head,the electromagnetic simulation model is obtained.2.Then,apply the finite element method to calculate the electromagnetic simulation model,obtain the radiation pattern of the mobile phone antenna at different frequencies and the specific absorption rate of the electromagnetic radiation of the human head by the mobile phone,and compare it with the control limit of the electromagnetic environment in my country to evaluate The safety of the human head exposed to the electromagnetic radiation of mobile phones.3.Finally,considering the uncertainty of the mobile phone’s electromagnetic radiation to the human head,the relevant parameters of the electromagnetic materials of different parts of the mobile phone are subject to different distribution types,and the Monte Carlo method is used to calculate the relevant statistical data to obtain the comparison results,and according to the relevant Different distribution types of parameters establish a generalized chaotic polynomial proxy model of the electromagnetic radiation of the mobile phone to the human head,use the stochastic response surface method to solve the proxy model to obtain the results,and then use the Sobol global sensitivity analysis method based on the generalized chaotic polynomial method to quantify different obedience The degree of influence of the input variables of the distribution type on the output of the system model is quantified to analyze the uncertainty of the electromagnetic radiation of the mobile phone on the human head.In summary,through the calculation of the established electromagnetic simulation model,the radiation pattern of the mobile phone antenna at different frequencies and the results of the specific absorption rate of the human head exposed to the electromagnetic radiation of the mobile phone are obtained,and the safety of the human head exposed to the electromagnetic radiation of the mobile phone is evaluated.,and by comparing the statistical characteristic information of the calculation results of the generalized chaotic polynomial method at different frequencies with the statistical characteristic information of the comparison results obtained by the Monte Carlo method,it is proved that the SAR calculation based on the generalized chaotic polynomial method is uncertain.Quantitative analysis is a solution to the uncertainty of the electromagnetic radiation caused by mobile phones to the human head.It can greatly reduce the time cost while ensuring the accuracy,and the Sobol global sensitivity analysis method based on the generalized chaotic polynomial method is calculated.The quantitative results of the influence of deterministic variables on the radiation received by the human head effectively evaluate the influence of the electromagnetic parameters of different components of the mobile phone on the electromagnetic radiation,and propose a proposal for the electromagnetic compatibility design and optimization of the electromagnetic radiation of the mobile phone to the human head scientific guidance.