摘要
推导了无线电窄波束在电离层中传输的非线性几何光学方程,分析了无线电窄波束在低电离层中传输的聚焦和散焦原理,推导出了散焦参数和聚焦参数的计算公式,研究了无线电窄波束在低电离层中传输的散焦现象,讨论了电波频率和功率对发散波束宽度的影响。计算结果表明:低电离层主要表现为一种散焦介质,使电波波束发散,当电波频率较低并且功率较大时,波束散焦现象非常明显,使到达目标点的功率密度大幅度降低,而当频率达到数GHz时,波束散焦现象很微弱。
A theoretical investigation of the principle of self-focusing and defocusing of narrow radio beam in lower ionosphere was presented, Nonlinear propagation equation, focusing parameter and defocusing parameter are deduced, which are used to analyze the microwave beam＇s width when propagating in lower ionosphere. Finally, the influence of frequency and microwave power on the final beam width is discussed. Results show that the lower ionosphere is mainly a defocusing material that will greatly reduce the microwave energy arriving at the destination, especially when the frequency is low and the radiating energy is high. But with frequency higher than several GHz, the defocusing is so weak that it can be ignored.
出处
《强激光与粒子束》
EI
CAS
CSCD
北大核心
2007年第5期811-814,共4页
High Power Laser and Particle Beams
基金
国家863计划项目资助课题
关键词
窄波束
低电离层
聚焦
散焦
Narrow radio beam
Lower ionosphere
Self-focusing
Self-defocusing
