Electromagnetic wave propagation characteristic test device in low temperature plasma

Abstract

The invention provides an electromagnetic wave propagation characteristic test device in low temperature plasma. The device comprises a plasma generation chamber, an annular high-voltage electrode and an annular ground electrode, wherein the annular high-voltage electrode and the annular ground electrode are arranged in the plasma generation chamber. The annular high-voltage electrode and the annular ground electrode are in insulation connection. The annular ground electrode is fixedly connected with the inner wall of the plasma generation chamber. The device uses the technology that electric potential difference is prevented inside plasma generated by glow discharge at low air pressure is used; the stable period of the generated plasma is prolonged, which is favorable for studying the propagation characteristic of electromagnetic waves of various frequency bands in the plasma; a good experiment environment is provided for studying absorption and scattering of incident electromagnetic waves of the plasma, tracking and identification technologies of a space exploration spacecraft which comes into atmosphere again, a plasma stealth technology, a plasma de-noising technology, a plasma antenna technology and the like; and the device has high scientific experimental application value and market prospect.

Description

technical field [0001] The invention belongs to the technical field of radio wave propagation experiments, and in particular relates to a device for testing electromagnetic wave propagation characteristics in low-temperature plasma. Background technique [0002] Plasma is composed of free electrons, positive ions and neutral atoms with equal charges, and is the fourth state of matter. As a special dispersion medium, plasma has unique absorption, reflection and scattering characteristics for electromagnetic waves; when electromagnetic waves propagate in plasma, its electric field will exert force on free electrons and positive ions, thus affecting the electromagnetic waves in plasma. The propagation characteristics of the plasma, especially the absorption and scattering of the incident plane wave by the plasma, are of great importance to the exploration of re-entry object tracking and identification technology, plasma stealth technology, plasma noise reduction technology and ...

AI Technical Summary

Problems solved by technology

The excitation tube method uses an explosion method to generate a supersonic shock wave, and generates plasma by compressing the gas in the test section. The time for this high-speed shock wave containing plasma to pass through the electromagnetic wave test area is only a few hundred microseconds. Among them, the stable period can only be maintained for about tens of microseconds; since the measurement of electromagnetic wave propagation characteristics must be completed within the stable period, high-speed sampling and timing trigger mechanisms are required, which makes the experiment difficult, inefficient and repeatable; In addition, the cavity used in the excitation tube method is mostly a quartz tube cavity, which is easily damaged and the experimental repeatability is poor.

On the other hand, artificial plasma uses microwaves, electric arcs, and plasma torches to generate plasma. Although it can work for a long time and is relatively stable, due to the high temperature in the environment, its electron density is difficult to measure and the control accuracy is low.

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