中文摘要：

雷电辐射电磁场的准确掌握对雷电定位、雷击过电压分析具有重要意义,基于矩量法重点分析了山体对雷电辐射场的影响。计算不考虑山体时的雷电辐射场,以前者的计算结果作为入射电磁波计算山体的散射,最终的雷电辐射场为两者的叠加。分析时,假设山体为介质体,分别讨论了山体的电阻率、高度、宽度以及山体距雷击点和观测点的距离对辐射场的影响,利用快速傅里叶变换得到相应的时域结果。计算结果表明了在一定范围内山体对雷电辐射场影响显著。对影响规律进行了总结。

英文摘要：

In order to acquire better knowledge of the lightning-radiated field, which is of great significance for both the remote measurement of lightning current and the analysis of coupled voltage in power line, the effects of large mountain in the propagation path on the lightning-radiated magnetic field were analysed. Based on the method of moment （MoM） general method to evaluate the scattering electromagnetic field from mountain was presented. Firstly the lightning-radiated magnetic field was calculated without consideration of the mountain. Then the scattering field of the mountain was determined with the above result taken as the incidence wave. The final observed lightning-radiated magnetic field is the sum of the mountain-scattering field and the lightning-radiated field above plane ground. In the investigation the mountain was considered to be dielectric body. And the resistivity, height and width of the mountain, as well as the distances from the lightning channel and the observed point to the mountain were all taken into account respectively. The corresponding time domain results were also derived by fast Fourier transformer （FFT）. The calculation indicates that the mountain affect the lightning-radiated field seriously in certain range. The general rule of the effect is concluded in the end.