Preliminary study of microwave diagnostics for transient plasma
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摘要: 采用微波诊断技术对气压300 Pa，S波段HPM条件下形成的低温、弱电离、非均匀和强碰撞大气等离子体特性参数开展了初步诊断研究。获取了9~15 GHz连续波穿过HPM等离子体区域的透射波形，并对波形进行了归一化处理；通过不同频率微波的透射特性，假设等离子体电子数密度分布呈Epstein分布，分析了可能的电子数密度最大值。该研究成果的获取为HPM大气等离子体在隐身、阻断信息链等方面的应用提供了重要的技术支撑。Abstract: Plasma characteristic is studied under conditions of microwave discharge in air with the microwave diagnostics technology. The plasma is cold, weakly ionized, no-uniform and collision with S band high power microwave. The transmission waveform with 9-15 GHz continuous wave passing the plasma region and pressure of 300 Pa is obtained and normalized. A discussion on the effect of various plasma parameters on transmitted power is presented. A parabolic plasma density profile is assumed across the Epstein Profile Model. The maximum plasma electron density is obtained by transmission waveform of various frequency. Characteristic study of microwave passing through the strong collision plasma provides significant technology support to applications of stealth technique and information blockage.
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Key words:
- high power microwave /
- plasma /
- microwave diagnostics /
- electron density /
- air breakdown
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图 5 压强300 Pa，脉宽τ=1 μs，fr=100 Hz放电区域结果
Figure 5. Discharge spot. p=300 Pa, τ=1 μs and fr=100 Hz
图 7 电场强度空间分布模拟仿真与实验测试结果比对
Figure 7. Comparison of experimental results and simulation results
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