Multi-peaked functions for representation of lightning channel-base currents

A new function is presented in this paper for representation of multi-peaked currents of lightning strokes. Experimentally measured lightning channel-base currents often have a few emphasized peaks. If such currents are approximated with a suitable analytical function, having analytical integral and derivative, lightning electromagnetic field is calculated based on some engineering, electromagnetic or other model of lightning strokes. For the function presented in this paper and two engineering models with new attenuation factors, calculated field results at different distances from the channel base are in better agreement with measurements. Analytically obtained Fourier transform of this function is useful for calculations of lightning electromagnetic field at a lossy ground.