Calculation and Research of Electromagnetic Fields in Space Around Lightning Path with finite difference time domain method

In this paper, numerical calculation method based on analytical formulas and FDTD are studied. A physical model for nature lightning is built in this paper, the lightning channel as a long ling wire, lightning current' s double exponential pulse time domain waveform. The numerical method from dipole formula is obtained by scattering lightning current at time and space, With finite difference time domain(FDTD) method, lightning space is dispersed and electromagnetic fields for whole free space are solved, with the computer program, the results are consistent with results of references and simulating test.