超宽谱电磁脉冲辐射场测量系统

Measurement system of ultra-wide spectrum electromagnetic pulse radiating field

介绍了一套自行研制的高功率超宽谱电磁脉冲辐射场测量系统,该系统主要由TEM喇叭接收天线、同轴传输线、宽带示波器及微型计算机组成。其中,TEM喇叭上极板为等腰三角形金属板,顶角14°,高60 cm,下极板为80 cm×30 cm矩形金属板,两金属板间夹角为7°,采用同轴线直接馈电方式,馈电点高度1mm。分析了测量系统的基本理论,采用时域有限差分和离散傅里叶变换相结合的方法对TEM喇叭接收天线的传递函数进行了计算,建立了信号衰减补偿方法。实测了抛物反射面脉冲辐射天线的辐射场,测得主轴上远区辐射场主脉冲波形与辐射天线的激励信号近似成微分关系,当激励信号的前后沿变快时,测得的辐射场也相应增大。测量结果表明,该系统能够反映脉冲辐射场的变化特性,具有良好的波形保真性和宽频带特性。

In this paper, a measurement system of UWS electromagnetic pulse radiating field is developed, which consisted of TEM horn, coaxial transmitting line, wide band oscillograph and data processing software for the compensation of signal attenuation and aberration. The TEM horn is fed vertically through coaxial line, its upper plate is an isosceles-triangle metal plate and lower plate is a rectangular metal plate. LabView is adopted to compile the data processing software. Pulses with base width from 300 ps to 4 ns can be measured accurately by using the system. The radiating field produced by a reflector antenna is measured,the experimental results show that the system has the characteristics of both the high waveform fidelity and the wide band. It can be applied in research of pulse radiation and transient field measurement.