Abstract:

The plasma frequency and the electron collision frequency can be deduced with the plasma diagnostic method that utilizing the transmission attenuation of microwaves at two neighboring (double) frequencies in a non-magnetized plasma. The process of attenuation measurement is presented,which utilizes a systemconsisted of a sweep oscillator, a pair of broad-banded horns, and a scalar network analyzer, etc. Errors of the diagnostic results are discussed. This method is suitable for the elementary diagnostics of a atmospheric-pressure plasma.

Key words: Plasma diagnostics, Double frequencies, Microwaves, Attenuation

摘要：

介绍了利用非磁化等离子体中微波在两个相邻波长处的透射衰减值来反推该等离子体频率(从而得到电子密度)和电子碰撞频率的方法───双频点微波透射衰减诊断方法。陈述了利用扫频信号源、标量网络分析仪和宽带喇叭天线等构成的系统对微波衰减测量的过程,对该方法的诊断误差进行了讨论。双频点微波透射衰减诊断法适用于大气压等离子体的初步诊断。

关键词: 等离子体诊断, 双频点, 微波, 衰减