| 查看: 297 | 回复: 3 | ||
| 【奖励】 本帖被评价3次，作者zhq025增加金币 3 个 | ||
| 当前主题已经存档。 | ||
[资源]
Fundamentals of the Physical Theory of Diffraction 2007
|
||
|
Preface The physical theory of diffraction (PTD) is a high-frequency asymptotic technique for the investigation of antennas and scattering problems. This monograph presents the first complete and comprehensive description of the modern PTD based on the concept of elementary edge waves (EEWs). Its subject is the diffraction of acoustic andelectromagneticwavesbyperfectlyreflectingobjectslocatedinahomogeneous losslessmedium. The basic idea of PTD is that:The diffracted field is considered as the radiation generated by the scattering sources (currents) induced on the objects. The so-called uniform and nonuniform scattering sources are introduced in PTD. Uniform sources are defined as sources induced on the infinite plane tangent to the object at a source point.Nonuniformsourcesarecausedbyanydeviationofthescatteringsurfacefrom thetangentplane.Forlarge convex objects with sharp edges, the basic contributions to the scattered field are produced by the uniform sources and by those nonuniform sourcesthatconcentratenearedges(oftencalledfringesources). Theintegrationofuniformsourcesleadstothephysicaloptics(PO)approxima- tionforthescatteredfield.ThePTDisthenaturalextensionofthePOapproximation, taking into accounttheadditional field createdbythenonuniform/fringe sources. Thisbookprovideshigh-frequencyasymptoticsforfringescatteringsourcesand for the scattered field in the far zone. Scattering characteristics are calculated for a variety of objects, such as strips, polygonal cylinders, cones, bodies of revolution withnonzeroGaussiancurvature(includingparaboloidsandsphericalsegments),and finitecircular cylinderswithflatbases. Thetitleofthebookunderlinesthefactthatagreatdealofattentionistobegiven to scattering physics. The derived analytic expressions clearly explain the physical structureofthescatteredfieldanddescribe,indetail,allofthereflectedanddiffracted rays and beams, as well as the fields in the vicinity of caustics and foci.Also, a new fundamentalcomponentofthefield,theso-calledshadowradiation,isintroduced.It isshownthatthiscomponentcontainshalf ofthetotalscatteredpower.Thephysical manifestations of the shadow radiation are the well-known phenomena of Fresnel diffraction andforwardscattering. Plotted numeric results supplement the theory and provide visualizations of the individualcontributionsofdifferentpartsofthescatteringobjectstothetotaldiffracted field.Detailedcommentsexplainallcriticalstepsintheanalyticandnumericcalcula- tionstofacilitatetheirexaminationandutilizationbyreaders.Allchaptersarefollowed by problems for independent investigations, which will be helpful in studying PTD, especiallyfor students. This book is intended for researchers working on antennas and scattering prob- lemsinindustryanduniversitylaboratories.Itcanalsobeusefulforteachingavariety ofuniversitycourses,thatincludetopicsonhigh-frequencyasymptotictechniquesin diffractiontheory.Universityinstructorsandgraduatestudentswillbenefitfromthis bookaswell. Download link：http://www.isload.com.cn/store/a4egq72doduid [ Last edited by zhq025 on 2008-1-16 at 10:56 ] |
回复此楼» 猜你喜欢
国自然申请面上模板最新2026版出了吗？
已经有15人回复
-
基金委咋了？2026年的指南还没有出来？
已经有4人回复
-
纳米粒子粒径的测量
已经有8人回复
-
疑惑？
已经有5人回复
-
计算机、0854电子信息（085401-058412）调剂
已经有5人回复
-
Materials Today Chemistry审稿周期
已经有5人回复
-
溴的反应液脱色
已经有7人回复
-
推荐一本书
已经有12人回复
-
基金申报
已经有4人回复
-
常年博士招收(双一流，工科)
已经有4人回复
简单回复
juntsing2楼
2008-01-02 21:04
回复
谢谢分享！