柱形等离子体辐射场的数值计算和分析

参照金属辐射场的求解方法，在简化条件下计算出柱形等离子体行波传输和驻波传输的辐射图．当改变等离子体密度以及相关参数时，对应的辐射图会相应地发生变化，得出与信号在金属介质中传输相类似的结果．根据理想柱形等离子体表面波的色散关系得到波矢，求出的柱形等离子体辐射方向图与金属介质的辐射方向图相比，会发生较大的变化，因此利用等离子体进行信号传输有一定的价值．

Numerical Computation and Analysis on Radiation Field of the Plasma Column

There are many ways to excite the plasma, surface waves can be used to excite the plasma from a single end. One of them is by means of capacitively coupled low-pressure Radio-frequency (RF) discharge, plasma surfaces can be suspended in free space to serve as antenna elements. The surface wave driven plasma antenna produces sufficiently low noise so as to be useful for broadcast communications. When frequencies well below the plasma frequency, the plasma surface wave also propagates near the speed of Light just as on a metal-dielectric interface. According to opproach of radiation pattern of metal, the radiation patterns of travelling wave and standing wave transmitting in a column plasma in simple conditions are calculated. When relevant parameters like plasma density are changed, radiation pattern also changes correspondingly. Compared with metal, there are similar results. Using wave vector from dispersion relation of the plasma surface wave for an ideal column plasma, radiation pattern will change greaterly compared with radiation pattern in metal. Radiation pattern of plasma column can be controlled by changing plasma parameters, so utilizing plasma to transmitting the signal, there are certain reference meanings.