金属介电常数对雷达目标散射截面的影响  

Impact of the metal permittivity on radar target scattering cross section

作　　者：杨洋[1,2] 景磊[1] 

机构地区：[1]天津大学精密仪器与光电子工程学院激光与光电子研究所,天津300072 [2]承德石油高等专科学校,河北承德067000

出　　处：《激光与红外》2013年第2期155-158,共4页Laser & Infrared

基　　金：国家重点基础研究发展计划项目(No.2007CB310403);"973"计划项目;高等学校博士学科点专项科研基金课题(No.20070420118)资助

摘　　要：金属目标的雷达散射截面除了与目标的大小、形状、入射角等有关外还与目标的电磁特性有关,电磁特性的核心就是金属的相对介电常数随频率的变化。低频情况下介电常数是复数,电磁波在导体表面产生感应电流会产生散射场,同尺寸非金属目标的雷达散射截面要远小于金属目标雷达散射截面;高频情况下,介电常数变为实数,金属不再是导体而是电介质了,可以像绝缘体一样反射和透射电磁波,同尺寸的非金属目标的激光雷达散射截面的数值可以大于金属目标的激光雷达散射截面。Apart from incidence angle, mental targets＇ size and shape, the radar scattering cross section（RCS） of men- tal targets is also related to the electromagnetic characteristics of the target. The essence of the electromagnetic proper- ties is that the relative dielectric constant of the metal changes with the electromagnetic frequency. At low frequency, metal permittivity is complex number. Induced current generated in the conductor surface by electromagnetic waves will produce a scattered field. RCS of non-mental targets is far less than that of the mental targets with the same size. At high frequency, metal dielectric constant is a real number. The metal is no longer a conductor but a dielectric, and has the same reflection as an insulator and transmits electromagnetic waves like an insulator. In this case, the RCS of the non-mental targets is greater than that of the mental targets with the same size.

关 键 词：金属介电常数 雷达散射截面 微波 红外 太赫兹 电磁特性 

分 类 号：TN958.98[电子电信—信号与信息处理]