DETERMINATION OF THE ELECTROMAGNETIC-FIELDS RADIATED FROM THE ARES EMP SIMULATOR

This paper describes a calculational model for evaluating the electrom agnetic (EM) fields produced by the ARES simulator outside its normal working volume. The model employs transmission line theory to determin e the simulator current distribution. Once this is determined, the rad iated fields are computed approximately using the Norton surface-wave formalism. The transient electric and magnetic fields on the ground ar e calculated using a fast Fourier transform (FFT) and are compared wit h experimental magnetic field data. Accuracies on the order of 30% in the peak fields are noted in much of the data. The fields in the air a bove the earth also have been calculated, and the relative importance of the Norton surface wave in the overall solution has been clarified. This model and its resulting PC code provide a useful tool for furthe r studies of the impact of radiated EM fields on distant electrical sy stems. The results presented here are directly applicable in defining and evaluating the EM environments produced by ARES, or by similar bou nded wave simulators, and in assessing and limiting the possible biolo gical effects of pulsed radiation.