非均匀等离子体覆盖金属目标的隐身性能分析

Stealth properties of metal target covered with non-uniform plasma

分析了非均匀冷等离子体覆盖金属目标的隐身性能。通过研究电磁波在多层媒质中的传播规律,建立广义反射系数公式,基于此公式,将非均匀冷等离子体均分成多层,每层可看作密度均匀分布,采用递推迭代的方法可得到从等离子体覆盖金属目标反射回来的电磁波,进而分析其回波损耗。数值结果表明,等离子体碰撞频率、厚度及密度是影响目标隐身的主要因素,增大碰撞频率、增加厚度可增大频段内的电磁波衰减,增加线性分布等离子体密度的最大值,能改善电磁波的最大衰减并提高有用衰减频段的中心频率。因此,统一优化等离子体覆盖物的相关参数,可以实现金属目标的最佳隐身效果。

Stealth properties of a metal target covered with non-uniform plasma are analyzed.By means of the study on the propagation of electromagnetic waves through multiple medium,the formula of general reflection coefficient is built.Non-uniform plasma is divided into many layers,and each layer could be uniform,then the reflected electromagnetic wave from the plasma covering target is obtained by using the method of recursive iteration for the formula of general reflection coefficient,with further dealing with the echo loss.The results show： plasma collision frequency,thickness and density are the main factors that influence the target stealth,the attenuation of electromagnetic waves in a frequency band will increase with the increase of plasma collision frequency and thickness,it can improve the maximum attenuation of electromagnetic waves and increase the center frequency of the attenuation frequency band by enhancing the maximum of the plasma density distribution.Therefore,by optimizing relevant parameters of plasma coverage,it can achieve the best stealth effect for metal targets.