摘要等离子体在隐身上有着得天独厚的优势。在查阅有关文献后,掌握了等离子体对电磁波的吸收过程。探究了等离子体的相关参数对电磁波衰减的影响。建立理论模型并进行了相关 模拟计算,模型中等离子体电子数密度范围为 1017m-3 到 1019m-3,等离子体碰撞频率范围为 1GHz-1000GHz,厚度为 0。3m。计算结果显示,等离子体对电磁波的吸收能力随 X 波段电磁波 的频率上升而下降;等离子碰撞频率有一个合适的范围,过低或者过高都会显著降低目标的 隐身效果;电子数密度也能改变等离子体的吸收电磁波的能力,在 1017m-3-1018m-3 内,电磁波 吸收率增长较为迅速,在 1018m-3 到 1019m-3 增长速度就较为缓慢了。电子数密度在某个范围内, 电磁波衰减会出现一个极大值,这意味着等离子体包裹的物体隐身能力得到极大的增强。同 时对单/双站雷达对等离子体吸收电磁波的研究发现,相较于单站雷达,表面覆盖了等离子层 的物体减少了双站雷达的探测难度,证明双站雷达在发现隐形战机上的确存在过人之处。这 些结论为等离子体在隐身方面的应用提供了理论参考。 79693
毕业论文关键词:隐身 等离子体 电子数密度 碰撞频率 雷达
Title Study of propagation characteristics of X-band electrmagnetic waves in low temperature plasma
Abstract The plasma has an unique advantage in stealth。 By reading the literature, the principal about how plasma absorb electromagnetic waves is known。 Some parameters of plasma can influence the absorption of electromagnetic waves。 Theoretical model and the related calculation are established。 In the model,Maximunm of the electron number density is 1019m-3,the range of plasma collision frequency is from 1GHz to 1000GHz。 Plasma thickness is 0。3m。 The study shows that the higher electromagnetic wave frequency,the less absorption of electromagnetic wave。 Appropriate Electron collision frequency range is necessary。Too higher or lower Electron collision frequency will decrease the invisibility effect significantly。 The electron number density can also influence invisibility effect。when the electron number density range is from 1017m-3to1018m-3,the electromagetic wave absorption will improve quickly。From 1018m-3to 1019m-3,the growth rate will decrease。And there is the range where the electromagetic wave absorption will increase rapidly。By the way,according to the study,apart from monostastic radar,the possibility of detection of bistatic radar is lower 。 This means that monostastic radar will be
replaced by bistatic radar 。The study shows the application of plasma in stealth theoretical reference
Keywords stealth , plasma , electron number density , collision frequency , radar
目录
1 引言 2
1。1 隐身等离子体技术介绍 2
1。2 国外等离子技术发展 2
1。3 国内等离子技术发展 3
1。4 等离子体对减少雷达散射截面(RCS)的意义 4
2。电磁波在等离子体中的传播和衰减 6
2。1 数学模型 6
2。2 传导方程 6
3。模拟计算结果与分析 9
3。1 电磁波频率对等离子体吸收效果的影响 10
3。2 等离子碰撞频率对等离子吸收效果影响 11
3。3 电子数密度对等离子体吸收效果影响