Direct or indirect effects of lightning may engender important damage on telecommunication network. This thesis discusses how theoretical study of the coupling mechanism of lightning can be achieved especially when the strike point is located near or on a structure composed of a telecommunication pylon. specifically, we outline a topological approach using software base on the transmission line theory (TLT) which allows us to characterise the surges induced on a telecommunication cable for different installation configurations. The coupling mechanism of lightning on a metal structure is carried out initially using an approximate method, then rigorously using the formalism of the antennas (FDTD). However, to take into account the whole of the physical phenomena, the development of new models, in particular the formalism of thin wire in dispersive medium is detailed.
