Scattering of a general partially coherent beam from a diffuse target in atmospheric turbulence

被引:0
作者
王利国 [1 ]
吴振森 [1 ]
王明军 [2 ]
曹运华 [1 ]
张耿 [1 ]
机构
[1] Science School,Xidian University
[2] Institute of EMWave Propagation & Scattering,Xianyang Normal College
关键词
atmospheric optics; extended Huygens–Fresnel principle; partially coherent beam; degree of coherence;
D O I
暂无
中图分类号
O357.5 [湍流(紊流)];
学科分类号
080103 ; 080704 ;
摘要
The second-order and fourth-order statistical moments of the speckle field from a diffuse target in atmospheric turbulence are studied which have great influence on the performance of lidar systems. By expanding a general rotationally symmetric beam as a sum of Gaussian–Schell model(GSM) beams, the mean intensity of the general beam propagating over a distance in an atmospheric turbulence is formulated. Expressions for the degree of coherence(DOC) and the normalized intensity variance of the scattered field of a general beam from a rough surface in turbulence are derived based on the extended Huygens–Fresnel principle. The general expressions reduce to the well-known forms for a GSM beam. Another example for the general beam used in this paper is the collimated flat-topped beam. The results of both kinds of beams show that the intensity profile on the target plane is a key factor affecting the statistical characteristics of the speckle field.A larger beam spot on the target plane induces a smaller coherence length and a smaller normalized intensity variance of the received field. As turbulence gets stronger, the coherence length becomes smaller, and the normalized intensity variance firstly increases and declines to unity finally.
引用
收藏
页码:209 / 215
页数:7
相关论文
共 1 条
[1]   斜程大气湍流中漫射目标的散射特性 [J].
韦宏艳 ;
吴振森 ;
彭辉 .
物理学报, 2008, (10) :6666-6672