对电磁波从辐射近区到远区特性的分析  

ANALYSIS OF THE CHARACTERISTICS OF ELECTROMAGNETIC WAVE RADIATION FROM THE NEAR ZONE TO THE FAR ZONE

作　　者：肖儿良[1] 刘婉 周征洋 艾聪 XIAO Erliang;LIU Wan;ZHOU Zhengyang;AI Cong(School of Optical-Electrical and Computer Engineering,University of Shanghai for Science and Technology,Shanghai 200093)

机构地区：[1]上海理工大学光电信息与计算机工程学院,上海200093

出　　处：《物理与工程》2024年第4期41-45,共5页Physics and Engineering

摘　　要：在大学物理关于电磁波辐射的教学中,重点讲解了电磁场在辐射近区和远区的特点。同学们认识到,对电偶极辐射,在辐射源附近,电场是与静场类似的纵波,而在远离辐射源的区域电磁波是横波。电场是怎样从纵波过渡到横波的呢?这个过渡区较为复杂,一般教科书上都没有仔细讲解,但这又是同学们非常关注的一个问题。因此,本文对电偶极、磁偶极和电四极辐射作了较完整的分析,并详细计算了电偶极辐射的电场从近区到远区的过程中,电场的纵向分量与横向分量的比值的变化,清晰地显示了从近场到远场的过渡过程。In the teaching of electromagnetic wave radiation in university physics,the focus is on explaining the characteristics of the electromagnetic field in the near and far zone of radiation.Students realize that in the case of electric dipole radiation,the electric field is a longitudinal wave similar to a static field near the radiation source,while in the region far from the radiation source,the electromagnetic wave is a transverse wave.How does the electric field transition from a longitudinal wave to a transverse wave?This transition zone is quite complex and is generally not explained in detail in textbooks.However,this is a question that students are very concerned about.Therefore,this article provides a detailed analysis of electric dipole,magnetic dipole,and electric quadrupole radiation,and calculates in detail the change in the ratio of the longitudinal component to the transverse component of the electric field during the process of electric dipole radiation from the near zone to the far zone,clearly showing the transition process from the near field to the far field.

关 键 词：电磁波辐射 纵场 横场 

分 类 号：G642.4[文化科学—高等教育学] O441.4-4[文化科学—教育学]