高功率宽谱开关振荡器

摘要

The generation and coupling out of high power wideband microwave based on the switched quarter-wavelength coaxial transmission line oscillator has been addressed. The switched oscillator works at 200 MHz, and is comprised of quarter-wavelength long coaxial transmission lines with a ring-shaped multichannel gaseous spark gap switch at one end. The coupler consists of blocking capacitor and distributed inductance. The generation and coupling out of wideband micorwave in the oscillator was simulated by commercial software. The switching characteristics were also studied. The results of simulation and experiment verify that directly-fed, high impedance and tooth socket structure can improve the stability of the multichannel switch. The wideband microwave generation system has been set up and charged by a high power Marx pulse source with output voltage of 500 kV. The center frequency of radiation is 195 MHz. The radiated peak electric field at a distance of 1 m is 150 kV and the full width at half maximum of frequency spectrum is about 30%.%采用1/4波长开关同轴谐振器技术路线,开展了高功率宽谱微波产生及耦合输出技术研究.设计振荡器工作在200 MHz.低阻抗1/4波长同轴传输线与传输线一端的环形多通道气体火花开关构成谐振器,耦台器由集中电容和分布电感构成,实现宽谱微波的能量提取.通过数值模拟研究了振荡器的振荡及耦合输出过程,分析了高压脉冲馈入方式、谐振器阻抗特性及开关齿槽结构对环形开关导通特性的影响.数值模拟和实验结果证明,采用直馈方式、高阻结构和齿槽结构有利于形成开关多通道导通,并提高开关导通的稳定性.在输出电压为500 kV的Marx脉冲功率源平台上构建了高功率宽谱微波产生实验装置,实验得到的宽谱微波振荡频率为195 MHz.辐射因子约150 kV,频谱带宽约30％.