Abstract
In this paper further theoretical investigations to understand and elucidate recently raised questions on the characteristics of lightning return-strokes curried out. Using Antenna Theory (AT) model, which is extended to take into account the channel inclination, the electromagnetic fields expressions for vertical dipole are completed, and an inclined channel is properly modeled, vertical electric and azimuthally magnetic fields are computed at different distances (close, intermediate and far distance ranges). The computations show that amplitudes and wave forms of the electromagnetic fields at close and intermediate lightning environment are considerably affected by the channel inclination.