摘要
基于瑞利近似推导了平面波入射下非均匀带电球形粒子的散射场及其散射截面,并通过数值仿真讨论了电荷非均匀分布对沙粒微分散射截面、散射效率的影响。数值结果表明:当沙粒表面电荷非均匀分布时,其微分散射截面呈明显空间分布,而电荷均匀分布时近似为各向同性散射;另外给定面电荷密度且电荷非均匀分布时带电沙粒散射效率远小于电荷均匀分布时的对应值,但在某些电荷分布角时恰好相反,随着沙粒带电量的增加其散射效率显著增加。由此说明在利用微波进行沙尘暴遥感或监测中需要同时考虑沙粒表面电荷分布规律及其携带电荷量的影响。
A new Rayleigh approximation for the scattering of electromagnetic wave by spherical sand with non-uniformly distributing charge is proposed, and some numerical simulation results on the differential scattering cross section（DSCS） and the scattering efficiency are discussed. The results show that, the DSCS presents an obviously spatial distribution while the charge is non-uniformly distributing on particles, but it shows an isotropic scattering property while the charge uniformly distributes on the sand. In addition, for a given charge density, the scattering efficiency for the former is much smaller than the one when the charge uniformly distributes on sand, but in some charged angle the law becomes contrary to the former law. These results illustrate that it is needed to consider the effect of the surface charge and its distribution form while using the microwave radar to monitor the dust storms.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2015年第12期279-285,共7页
Acta Optica Sinica
基金
国家自然科学基金(11302111、41305035、11562017、41305027)
科技部国际合作项目(2011DFA11780)
上海交通大学先进光通信系统与网络国家重点实验室开放课题(2013GZKF031306)
宁夏自然科学基金联合基金项目(NZ12117)
关键词
物理光学
电磁波散射
瑞利近似
沙粒带电
非均匀分布
physical optics
electromagnetic scattering
Rayleigh approximation
charged sand
non-uniformly distributing charge
