Statistical Analysis of Electric Field Waveforms Produced by Lightning Return Stroke

낙뢰에 의해서 발생되는 전장파형의 통계적 분석

In this paper, in order to obtain statistical informations on lightning electromagnetic waveforms, electric field waveforms produced by lightning return strokes were measured and analyzed. The electric field measuring system consists of hemisphere antenna 30[cm] in diameter, integrator and data acquisition. system. The frequency bandwidth of the measuring system is 200[Hz] to 1.56[MHz], and the sensitivity is 0.96[mV/V/m]. The mean value of front time of electric field waveforms produced by positive lightning return strokes is 5.87[${\mu}s$], and that of negative is 4.12[${\mu}s$]. The mean values of zero-crossing time for positive or negative electric field waveforms are 35.00 and 26.61[${\mu}s$], respectively. The mean value of percentage dip-depth for positive electric field waveforms is 33.68[%], and that for negative is 28.36[%].