Near Field Characteristics Of Electromagnetic Radiation From Mobile Base Station In Complex Environment Research On Environmental Impact Assessment Method

In this paper,the research object is the analysis and evaluation method of electromagnetic radiation environmental impact of mobile base station.According to the data collected from the preliminary investigation,data review and relevant personnel visit,the current situation of the external environment of the base station is monitored at the same time.On this basis,the field test data are analyzed,and the corresponding data are obtained with the simulation model for further comparative simulation,so as to provide technical basis for the evaluation of the electromagnetic radiation near-field area of the base station.In the study of typical cases,the corresponding base station electromagnetic radiation environment impact analysis and evaluation methods are obtained,and the electromagnetic radiation environment management evaluation and principle suggestions are proposed.The main achievement of this essay is outlined below :(1)Theoretical analysis of electromagnetic radiation characteristics of mobile base stationIn the near field simulation and analysis technology of electromagnetic radiation of mobile base station,the empirical formula of near field radiation of mobile base station antenna and environmental characteristics are established in combination with the system characteristics to construct the simulation calculation and analysis software.With the establishment of the simulation model of typical base station electromagnetic environment,the distribution law of electromagnetic radiation in the near-field area of mobile communication base station and the difference between the characteristics of electromagnetic radiation in the far-field area and that in the far-field area are quantitatively studied.It is concluded that as long as the measurement position is within the half power beam width of the main beam in the far-field pattern of the antenna,the power density calculated by the far-field formula can be guaranteed to be greater than that of the electromagnetic simulation software Near field radiation simulation value.(2)Measurement and verification of electromagnetic radiation from mobile base stationBased on the characteristics of mobile communication base station,the model of antenna near-field test is established,and the corresponding data processing method is formed.In general,the stronger the antenna power is,the larger the calculated field strength is,and the more points beyond the threshold appear.This provides the technical basis for the evaluation of the electromagnetic radiation of the base station.(3)Research on the environmental impact analysis and evaluation method of electromagnetic radiation in the near field of mobile base station.The method of environmental impact analysis and evaluation of electromagnetic radiation in the near-field area of base station is studied.With typical case study,it is conservative and feasible to calculate the power density in the near-field area of antenna by far-field formula.This will simplify the calculation method of near-field area,and put forward the management principle of electromagnetic radiation environment for base station construction.