Prediction Research On Electromagnetic Radiation Of Base Station Based On Polarization Wave Power Distribution And Polarization Matching Coefficient

With the continuous growth of mobile communication services and the application of 5G communication system,a large number of new base stations need to be built.Therefore,it is very important to accurately measure and predict the electromagnetic radiation intensity of the base stations.At present,the dual-polarized antenna is commonly used in base station transmitting antenna.Because polarization attributes of polarized wave will change in complex propagation environment,there will be a certain distribution of polarized wave power in space.Without considering the distribution of polarized wave power,it is difficult to accurately predict and evaluate its electromagnetic radiation.On the other hand,in the prediction of electromagnetic radiation,there are always deviations between the polarization direction of antenna and the polarization wave direction.The polarization matching coefficients between them need to be considered in order to obtain the accurate prediction value of electromagnetic radiation.In view of the existing problems,the main work and innovation of this paper are as follows:(1)In this paper,a prediction method of electromagnetic radiation based on power distribution of polarized wave is proposed.The method establishes the power distribution model of polarization wave based on piecewise function by analyzing the distribution of vertical polarization wave and horizontal polarization wave power in spatial angle,and then gets the relevant parameters by fitting the piecewise function model through the measurement of electromagnetic radiation at different spatial angles,so as to obtain the accurate electromagnetic radiation prediction value of base station.In fitting the polarization wave power distribution model,it is found that the polarization wave power distribution model based on piecewise function is more accurate than Laplace model and Gaussian model,and its R-square value tends to be 1,and the fitting effect is better.In the actual measurement of building areas on four sides,the relative error between the predicted and measured values of electromagnetic radiation in this paper is 0.068,in the three sides of the building area,the relative error is 0.021,and in the forest shelter area,the relative error is 0.048,which verifies the effectiveness of this method.(2)In this paper,a prediction method of base station electromagnetic radiation based on polarization matching coefficient is proposed.In this method,the polarization unit vectors of base station transmitting antenna and electromagnetic radiation measuring antenna are obtained,and then the polarization matching coefficients are obtained through the polarization unit vectors of both antennas,so as to obtain the accurate prediction value of base station electromagnetic radiation.By comparing the measured and predicted values of the horizontal polarization measurement antenna and the vertical polarization measurement antenna,it is found that when the horizontal distance is close to the base station,the error is larger,but the horizontal distance is greater than 15 m,the error becomes smaller.At the same time,from the analysis between the measured and predicted values of total electromagnetic radiation intensity,we can see that the root mean square error Re value between them is relatively small,0.052,and the uncertainty U value is equal to 0.5324,which indicates that the deviation between the measured and predicted values of total electromagnetic radiation intensity is small and has better accuracy.