Lightning electromagnetic field is obtained by using ââ?¬Å?engineeringââ?¬Â models of lightning return strokes and new channel-base\r\ncurrent functions and the results are presented in this paper. Experimentally measured channel-base currents are approximated\r\nnot only with functions having two-peaked waveshapes but also with the one-peaked function so as usually used in the literature.\r\nThese functions are simple to be applied in any ââ?¬Å?engineeringââ?¬Â or electromagnetic model as well. For the three ââ?¬Å?engineeringââ?¬Â models:\r\ntransmission line model (without the peak current decay), transmission line model with linear decay, and transmission line model\r\nwith exponential decay with height, the comparison of electric and magnetic field components at different distances from the\r\nlightning channel-base is presented in the case of a perfectly conducting ground. Different heights of lightning channels are also\r\nconsidered. These results enable analysis of advantages/shortages of the used return stroke models according to the electromagnetic\r\nfield features to be achieved, as obtained by measurements.
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