Файл: Ufimtsev P. Fundamentals of the physical theory of diffraction (Wiley 2007)(348s) PEo .pdf

strip, 83–99

total scattered field and, 87–92 Dirichlet condition, 6

Disk

diffraction, multiple edge waves and, 261–268

scattering, 126–127

nonuniform, field generated, 130–132 physical optics approximation, 127–130 total scattered field, 132–134

Edge

diffracted waves

caustic asymptotics, 213–226 ray asymptotics, 213–226

waves

electromagnetic, 169–210 multiple diffraction, 229–245

grazing incidence, 229–245 grazing, 230–236

slope, 229–245

EEW (elementary edge waves) analytic properties of, 187–191

diffraction cone, 190–191 electromagnetic, 194–198 general asymptotics, 183–187

grazing singularity

(1) nonuniform component j , 204–205

removal of, 198–208

high frequency asymptotics, 169 history of, 209–210

important points, 175

other interpretations of, 209–210 nonuniform, 192–193

numerical calculations of, 191–194 one dimensional integrals, 178–183 triple integrals, 175–177

transformation of, 178–183 Electromagnetic

diffraction problems, 5–31 EEW, 194–198

grazing singularity removal and, 203–208

waves, 27–31, 129–130 backscattering finite length cylinder,

279–284

caustic asymptotics and, 225–226 diffraction interaction and, 252–254

Index 325

edge, 169–210

E-polarization, 279–283, 304–306 finite length cylinder bistatic scattering

and, 304–310

grazing diffraction and, 234–236 H-polarization, 283–284, 306–308 multiple diffraction, 267–268

ray asymptotics and, 218–219 Shadow Contour Theorem, 30 shadow radiation, 16–21

slope diffraction and, 238–240, 243–245

specular beam, refined asymptotics, 308–310

uniform component, 28 Elementary edge waves (EEWs), 169 Elementary strips

canonical wedge, 170–171 js,h(1) integrals, 171–175

E-polarization, 279–283, 304–306 Exact solution, 33–56

Extended Kirchoff Approximation (KA). See scalar physical optics.

Far zone, 7–10

bistatic cross-section, 9

Field generated nonuniform scattering sources, 130–132

Field us,h(1) Bessel interpolations, 125–126 Finite length cylinder

backscattering, 269–284 acoustic waves, 269–279

electromagnetic waves, 279–284 bistatic scattering, 287–310

acoustic waves, 287–304 electromagnetic waves, 304–310

First order diffraction

polygonal cylinders, 83–112 strips, 83–112

triangular cylinder, 99–112 PTD

approximation

backscattering and, 107–109 symmetric scattering and,

104–107

asymptotics, bodies of revolution and, 145

Hankel function, 96

326 Index

First order (Continued ) PTD (Continued )

strip diffraction and, 95–99 TED approximation, 99

truncated scattering sources, 95–99 Focal field

cone scattering and, 134–141 canonical conic surface diffraction and,

124–125 Fock, theory of, 10

Fresnel integral, 48, 50, 53 Fringe waves, 26 Functions

f (1) integrals, 76–78 g(1) integrals, 76–78

Geometrical acoustics, 9–10

Geometrical optics. See uniform component. GO boundary, PTD field and, 161 Gradshteyn and Ryzhik table formula, 60 Grazing

diffraction, 230–236 acoustic waves, 230–234

electromagnetic waves, 234–236 edge waves multiple diffraction and,

229–245

(1)

EEW, nonuniform component j , 204–205

singularity, removal of, acoustic EEW, 199–203 EEW and, 198–208

electromagnetic EEW, 203–208

(0) ≡ (hp) uniform component j j ,

205–208 Green theorem, 36, 39

Hankel function, 35, 80, 96 integral forms, 60

Hard

diffraction, multiple, 261–264

fringe field, acoustic wave backscattering and, 278

Helmholtz

equivalency theorem, 17 integral expressions, 7

High frequency asymptotics, elementary edge waves and, 169

H-polarization, 283–284, 306–308

Incident plane wave, 40

Incomplete asymptotic expansion, multiple soft diffraction and, 258–260

Induced surface field nonuniform component, 25–27 uniform component, 25–27

Integrals

functions f (1), 76–78 functions g(1), 76–78

nonuniform components and, 71

js,h(1) integrals, elementary strips and, 171–175

Laplacian operator, 34

Monstatic cross section, 9 Multiple

acoustic edge waves, diffraction convex body of revolution, 255–260

diffraction

edge waves and, 229–245 electromagnetic waves, 267–268

edge waves

disk diffraction, 261–268 hard diffraction, 261–264

hard diffraction, 256–264

soft diffraction, incomplete asymptotic expansion, 257–260

Neighboring edges diffraction interaction, ruled surface, 247–254

Neuman condition, 6 Nonuniform

component, 25–27

(1), grazing singularity, EEW and, j

204–205

j(1), backscattering acoustic waves and, 273–277

radiation asymptotics, 71

integrals, 71

functions f (1), 76–78 functions g(1), 76–78

surface sources, 71–82 diffraction part, 26 fringe waves, 26

physical optics diffracted field and, 68

disk scattering, field generated, 130–132 EEW, 192–193

Nonzero Gaussian curvature

axially symmetric bistatic scattering, 155–156

bodies of revolution and, 141–156 Numerical analysis

paraboloids backscattering and, 147–151 scattered field and, 92–95, 110–111 spherical segment backscattering and,

153–155

Oblique incidence Hankel function, 80 plane wave and, 78–82

One dimensional integrals, EEW and, 178–183

Optical theorem,15

Paraboloids backscattering, 145–151 asymptotics, 145–147

numerical analysis, 147–151 Pascul, pressure unit, 7

Pauli

asymptotics, 47–51 Fresnel integral, 48 Sommerfeld ray, 51 Taylor series, 47

technique, uniform asymptotoic, 51–55 Fresnel integrals, 53

Taylor series, 52 Physical optics (PO)

approximation, 101–102, 127–130 acoustic waves, 127–129

backscattering and, 269–272 backscattering, 102–104 bistatic scattering and, 287–288

bodies of revolution and, 143–144 electromagnetic waves, 129–130

canonical form conversion, 61–67 Cauchy residue theorem, 63

definition of, 11–13 diffracted field

nonnuniform components, 68 ray asymptotics, 67–68

diffraction problems and, 11–25 equations, 13

Index 327

field

axially symmetric bistatic scattering and, 156–159

Bessel interpolations, 159–160 bistatic scattering and, 289–290 ray

asymptotics, 156–159 region, 161–165

reflected rays, shadow region, 165–166 shadow radiation, 289–290

transition region, 161–165 wedge diffraction and, 59–68

geometrical optics, 11 optical theorem, 15 original integrals, 59–61

Gradshteyn and Ryzhik table formula, 60

Hankel function, 60 Sommerfeld formula, 61

part, strip diffraction and, 85–87 properties of, 24–25

scalar, 13 shadow

contour theorem, 21–24 radiation, 16–21

total scattering cross section, 13–15, 21–24

uniform components, 12, 59 uniform components, 59

Physical theory of diffraction (PTD) approximation, first order, 104–109 asymptotics, first order, 145 bistatic scattering, 290–296

field

axially symmetric bistatic scattering and, 160–161

Bessel interpolations, 160–161 GO Boundary, 161

first order, 95–99

physical theory of diffraction, 5–7 scattered field, 7–10

Plane wave

excitation transition, 38–40 Green theorem, 39 incident plane wave, 40

Sommerfeld radiation condition, 39 oblique incidence, 78–82

PO. See physical optics. Polygonal cylinders, 83–112

328 Index

Poynting vector for electromagnetic waves, 5 Pressure unit, Pascul, 7

PTD. See physical theory of diffraction.

Radiation

nonuniform component, surface sources, 71–82

wedge diffraction and, 71–82 Ray

asymptotics

acoustic waves, 213–217

diffraction, canonical sonic surface and, 118–124

edge diffracted waves and, 213–226 electromagnetic waves, 218–219 physical optics diffracted field and,

67–68

PO field and, 156–159 bistatic scattering and, 297–300

component. See uniform component. region, PO field and, 161–165

Reflected rays, shadow region, 165–166 Ruled surface, neighboring edges diffraction

interaction, 247–254

Ryzhik and Gradshteyn table formula, 60

Scalar physical optics, 13 Scattered

field

far zone, 7–10

Helmholtz integral expressions, 7 integrals, canonical conic surface and,

117–118

numerical analysis, 92–95 PTD and, 7–10

strip diffraction and, physical optics part, 85–87

theory of Fock, 10 total, 132–134

sources, first order PTD and, 95–99 Series solution, 40–44

conversion to Sommerfeld integrals, 40 Shadow

contour theorem, 21–24 radiation, 12–21

Helmholtz equivalency theorem, 17 physical optics field and, 289–290

region, reflected rays and, 165–166

Slope diffraction, 236–240

acoustic waves, 236–238, 240–243 edge waves and, 229–245

electromagnetic waves, 238–240, 243–245 Smooth convex, 9

Soft

diffraction, multiple, 261–264

fringe field, acoustic wave backscattering and, 278

Sommerfeld formula, 61 integrals

Bessel function, 40 Cauchy theorem, 41

series solution conversion to, 40 radiation condition, 39

classical form, 40 ray asymptotics

diffracted ray, origin of, 46 Pauli, 47–51

wedge diffraction and, 44–47 Specular beam

bistatic scattering and, 300–304 electromagnetic waves and, refined

asymptotics, 308–310 refined asymptotics, 300–304

Spherical segment backscattering bodies of revolution and, 151–155 numerical analysis, 153–155

Steepest descent method, 44 Strip diffraction, 83–99

first order PTD, 95–99

scattered field, physical optics part, 85–87 total scattered field, 87–92

Strips, first order diffraction, 83–112 Surface sources, nonuniform component

radiation and, 71–82 Symmetric scattering

first-order PTD approximation, 104–107 PO approximation, 101–102

Taylor series, 47, 52

TED approximation 92, 99 Theory of Fock, 10

Total

field, backscattering acoustic waves and, 277–279

hard fringe, 278 soft fringe, 278