Abstract: Aiming at clarifying the interference effect of 5G electromagnetic radiation on relay protection and

communication control equipment in converter station，a microstrip antenna simulation model with a center

frequency of 3.5 GHz was established. Firstly，the propagation and attenuation law of electromagnetic radiation of

microstrip antenna was analyzed. It is found that due to the asymmetry of microstrip patch，the gain of the direction

directly above or below the normal direction of the patch is significantly higher than that of other directions.

Secondly，taking air as the control group，the interference suppression ability of PVC plastic，concrete and stainless steel plate was analyzed respectively. It is found that stainless steel plate had better electromagnetic interference shielding ability than the other two materials. Finally，in order to ensure the normal communication needs of the monopole antenna in the shielding box，the layout of stainless steel shielding box was optimized，and the external electromagnetic interference was reduced from 66.5 dB to 30 dB by uniformly excavating 5 mm through holes on the box. The research results provide a useful reference for clarifying the spatial propagation law of 5G radiation of microstrip antenna and the reasonable selection of shielding measures.

      Key words: 5G communication technology；electromagnetic radiation（EMR）；gain；shielding material；interference suppression