基于冲击脉冲辐射天线的高功率超宽带电磁脉冲辐射系统

High-Power Ultra-Wideband Electromagnetic Pulse Radiation System Based on the Impulse Radiating Antenna

为给超宽带电磁脉冲效应机理与防护技术的研究提供实验平台,研制了一种基于冲击脉冲辐射天线(impulse radiation antenna,IRA)的高功率超宽带电磁脉冲辐射系统,辐射系统由差分脉冲高压源、锋化开关、IRA和介质透镜等部分构成。设计中,差分脉冲高压源由基于氢闸流管的脉冲源驱动副边中心抽头的脉冲变压器实现;设计的紧凑型锋化开关高度仅为1 cm,开关间隙为1 mm,可嵌入IRA天线馈电点,开关最高工作气压可达3 MPa;基于菲涅尔定理设计了介质透镜,以校正锋化开关和绝缘变压器油对IRA天线辐射中心的影响,改善了天线的辐射特性;辐射系统可通过改变锋化开关的气压和充电电压调节系统辐射功率。测试实验表明辐射系统的主要技术参数如下:在时域,在天线主轴距离口径面5.5 m处辐射电场脉冲上升沿约为330 ps,幅值约为±8 kV/m,远场有效电势最高可达44 kV,辐射功率可调;在频域,中心频率为400 MHz,基于能量范数比定义的信号频带为80 MHz~1GHz,信号带比约为12.5,百分比带宽为170.4%。辐射系统能够为开展超宽带电磁脉冲效应阈值规律及防护技术的研究提供一个辐射功率可调的试验平台。

In order to provide an experimental platform for research on ultra-wideband electromagnetic pulse effect mechanism and protection technology,a high-power ultra-wideband electromagnetic pulse radiation system based on impulse radiation antenna(IRA)is developed.The radiation system is composed of a differential high-voltage pulsed source,a peaking switch,an IRA,and a dielectric lens.In the design,the differential pulsed source is realized by the pulse source based on hydrogen thyristor driving the pulsed transformer with secondary side center tapped.The designed compact peaking switch has a total height of only 1 cm and a switch gap of 1 mm.It can be embedded at the feeding point of IRA antenna,and the maximum working pressure of the switch can reach 3 MPa.Based on the Fresnel’s theorem,a dielectric lens is designed to correct the influence of high-voltage gas switch and insulating transformer oil on the radiation center of IRA and improve the radiating performance of the antenna.The radiation system can adjust its radiation power by changing the air pressure and charging voltage of the gas switch.The test results show that the main technical parameters of the radiation system are as follows:in the time domain,the rising edge of the radiation electric field pulse is about 330ps,the amplitude is about±8 kV/m,the far-field effective potential is up to 44 kV,and the radiation power is adjustable;In the frequency domain,the center frequency of the radiating field is 400 MHz,the frequency band defined based on the energy norm ratio is 80 MHz~1 GHz,and the band ratio is about 12.5,which means the percentage bandwidth is 170.4%.The radiation system can be used as a test platform for the research of UWB electromagnetic pulse effect threshold and protection technology.