Propagation, scattering, and dissipation of electromagnetic waves

289 Pages·1993·12.61 MB·English

by  Slepi︠a︡n, G. I︠A︡, Ilʹinskiĭ, A. S., Slepyan, A. Ya

ElEctromagnEtic wavEs sEriEs 36
Propagation,
scattering and dissipation
of electromagnetic waves
A. S. Ilyinsky,
G. Ya. Slepyan
and A. Ya. Slepyan
Peter Peregrinus Ltd. on behalf of the Institution of Electrical Engineers
IEE ELECTROMAGNETIC WAVES SERIES 36
Series Editors: Professor P. J. B. Clarricoats
Professor Y. Rahmat-Samii
Professor J. R. Wait
Propagation, scattering
and dissipation of
electromagnetic waves
Other volumes in this series:
Volume 1 Geometrical theory of diffraction for electromagnetic waves
G. L. James
Volume 2 Electromagnetic waves and curved structures L. Lewin,
D. C. Chang and E. F. Kuester
Volume 3 Microwave homodyne systems R. J. King
Volume 4 Radio direction-finding P. J. D. Gething
Volume 5 ELF communications antennas M. L. Burrows
Volume 6 Waveguide tapers, transitions and couplers F. Sporleder and
H. G. Unger
Volume 7 Reflector antenna analysis and design P. J. Wood
Volume 8 Effects of the troposphere on radio communications
M. P. M. Hall
Volume 9 Schumann resonances in the earth-ionosphere cavity
P. V. Bliokh, A. P. Nikolaenko and Y. F. Flippov
Volume 10 Aperture antennas and diffraction theory E. V Jull
Volume 11 Adaptive array principles J. E. Hudson
Volume 12 Microstrip antenna theory and design J. R. James, P. S. Hall
and C. Wood
Volume 13 Energy in electromagnetism H. G. Booker
Volume 14 Leaky feeders and subsurface radio communications
P. Delogne
Volume 15 The handbook of antenna design, Volume 1 A. W. Rudge,
K. Milne, A. D. Olver, P. Knight (Editors)
Volume 16 The handbook of antenna design, Volume 2 A. W. Rudge,
K. Milne, A. D. Olver, P. Knight (Editors)
Volume 17 Surveillance radar performance prediction P. Rohan
Volume 18 Corrugated horns for microwave antennas P. J. B. Clarricoats
and A. D. Olver
Volume 19 Microwave antenna theory and design S. Silver (Editor)
Volume 20 Advances in radar techniques J. Clarke (Editor)
Volume 21 Waveguide handbook N. Marcuvitz
Volume 22 Target adaptive matched illumination radar D. T. Gjessing
Volume 23 Ferrites at microwave frequencies A. J. Baden Fuller
Volume 24 Propagation of short radio waves D. E. Kerr (Editor)
Volume 25 Principles of microwave circuits C. G. Montgomery,
R. H. Dicke, E. M. Purcell (Editors)
Volume 26 Spherical near-field antenna measurements J. E. Hansen
(Editor)
Volume 27 Electromagnetic radiation from cylindrical structures
J. R. Wait
Volume 28 Handbook of microstrip antennas J. R. James and P. S. Hall
(Editors)
Volume 29 Satellite-to-ground radiowave propagation J. E. Allnutt
Volume 30 Radiowave propagation M. P M. Hall and L. W Barclay
(Editors)
Volume 31 Ionospheric radio K. Davies
Volume 32 Electromagnetic waveguides: theory and application S. F. Mahmoud
Volume 33 Radio direction finding and superresolution P. J. D. Gething
Volume 34 Electrodynamic theory of superconductors S.-A. Zhou
Volume 35 VHF and UHF antennas R. A. Burberry
Propagation, scattering
and dissipation of
electromagnetic waves
A. S. Ilyinsky,
G. Ya. Slepyan
and A. Ya. Slepyan
Peter Peregrinus Ltd. on behalf of the Institution of Electrical Engineers
Published by: Peter Peregrinus Ltd., on behalf of the Institution of
Electrical Engineers, London, United Kingdom
© 1993: Peter Peregrinus Ltd.
Apart from any fair dealing for the purposes of research or private study,
or criticism or review, as permitted under the Copyright, Designs and
Patents Act, 1988, this publication may be reproduced, stored or
transmitted, in any forms or by any means, only with the prior permission
in writing of the publishers, or in the case of reprographic reproduction in
accordance with the terms of licences issued by the Copyright Licensing
Agency. Inquiries concerning reproduction outside those terms should be
sent to the publishers at the undermentioned address:
Peter Peregrinus Ltd.,
The Institution of Electrical Engineers,
Michael Faraday House,
Six Hills Way, Stevenage,
Herts. SG1 2AY, United Kingdom
While the authors and the publishers believe that the information and
guidance given in this work is correct, all parties must rely upon their own
skill and judgment when making use of it. Neither the authors nor the
publishers assume any liability to anyone for any loss or damage caused
by any error or omission in the work, whether such error or omission is
the result of negligence or any other cause. Any and all such liability is
disclaimed.
The moral right of the authors to be identified as authors of this work has
been asserted by them in accordance with the Copyright, Designs and
Patents Act 1988.
British Library Cataloguing in Publication Data
A CIP catalogue record for this book
is available from the British Library
ISBN 0 86341 283 1
Printed in England by Antony Rowe Ltd., Wiltshire
Contents
Page
Preface vi
List of notations x
1 Introduction 1
1.1 Los reduction in microwave waveguides and resonators 1
1.2 Maxwel's equations; constitutive equations; boundary conditions 4
1.3 Solution techniques for mathematical problems of electromagnetics 7
1.4 Acuracy control and computational instabilities 14
2 Surface-impedance technique for the study of dissipation processes
in bodies with finite conductivity 18
2.1 The Leontovich impedance boundary condition 18
2.2 The surface impedance of normal metals for the anomalous skin effect 20
2.3 Surface impedance of superconductors 24
2.4 Surface impedance modification for structures with edges 26
2.5 The edge condition for an impedance halfplane located at media interface 32
3 Normal modes in waveguides with loses 37
3.1 Excitation of waveguides without loses 37
3.2 Excitation of waveguides with loses in the wals 41
3.3 Eigenmodes in waveguides; dispersion characteristics 43
3.4 Asociated waves 50
3.5 Types of dispersion characteristics; a concept of anomalous dispersion;
complex waves in losles waveguides 53
3.6 Excitation of TM modes in a parallel-plate impedance waveguide 55
3.7 Atenuation coeficients of eigenmodes 59
3.8 Attenuation in a generalised microstrip line; model of the infinitely thin
strip 65
3.9 Attenuation in a microstrip line; model of a strip of finite thickness 70
3.10 Atenuation in a microstrip line; numerical results 75
vi Contents
4 Normal oscilations in resonators with loses 83
4.1 Expansion of eigenoscillations of a resonator with losses in the walls in
terms of resonant modes of an identical losles resonator 83
4.2 Resonance frequencies and (^-factors of eigenoscilations 86
4.3 Eigenoscillations and free oscillations in a resonator with a magneto-
dielectric absorbing body 90
4.4 Q;factor of a cylindrical cavity 97
4.5 (^-factor of spherical and conical cavities 9
4.6 Galerkin's method for calculation of a complex-shaped cavity resonator
in the form of a body of revolution 104
4.7 Cylindrical resonator with dielectric slabs 111
4.8 Q;factor of a cylindrical resonator with a coaxial insert 114
5 Electromagnetic-wave diffraction by finitely conducting comb-shaped
structures 123
5.1 Diffraction of a plane wave by an array of impedance halfplanes:
H-polarisation 123
5.2 Diffraction of a plane wave by an array of impedance halfplanes:
E-polarisation 129
5.3 Diffraction by a finitely conducting comb-shaped structure 135
5.4 Perturbation technique 140
5.5 Effect of abnormally small absorption in periodic structures 141
5.6 Absorption in inclined comb-shaped structures and echelettes 149
5.7 Diffraction by a complex-shaped periodic structure: integral equation
method 153
5.8 Diffraction by a complex-shaped periodic structure: Galerkin's incomplete
method with semi-inversion 16
6 Dissipation in comb-shaped structures in inhomogeneous and
anisotropic media 179
6.1 Diffraction by finitely conducting comb-shaped structure with a layered
dielectric filing; resonance absorption 180
6.2 Wave diffraction by comb-shaped structures in gyrotropic media 185
6.3 Nonreciprocal resonance efects 190
7 Eigenmodes in corrugated waveguides and resonators with finitely
conducting wals 196
7.1 Eigenmodes in periodic structures f 196
7.2 Equivalent boundary conditions for finitely conducting comb-shaped
structures 201
7.3 Surface waves in finitely conducting comb-shaped structures 206
7.4 TM modes in plane comb-shaped waveguides 207
7.5 Attenuation in waveguides with azimuthal corrugation 212
7.6 Projection method for calculation of propagation and attenuation
coefficients of corrugated waveguides with arbitrary shapes of cross-section
and corugation 216
7.7 Propagation characteristics of circular corrugated waveguides 223
7.8 Attenuation characteristics of circular corrugated waveguides 227
7.9 Millimetre-waveband high-quality corrugated resonators 231
7.10 Radiation from a corugated horn 240
References 248
Appendix 1 Shooting method and its modifications 257
Contents vii
Appendix 2 Expressions for current-density distributions in a microstrip line
with a strip of finite thicknes 268
Appendix 3 General formulae for the coefficients a^ , P^, y^, <5j£J, 272
Index 275
Preface
Textbooks and monographs on microwave theory contain very little material
on methods of calculating microwave absorption. However, problems do exist
in this field which is confirmed by the vast amount of journal publications on
the issue, especially during the last decade. There are some mutually contradic-
tory views concerning a number of aspects and arguments about resolved
questions regularly arise.
This is largely due to the absence of a monograph dealing with the problems
of electromagnetic wave absorption in waveguides, resonators and periodic
structures. This book attempts to fill the gap.
The introduction reviews possible ways of reducing losses in waveguides and
resonators, it formulates boundary-value problems of electromagnetics for cases
when losses are considered, and gives analytical and numerical methods of
analysis. Chapter 2 deals with the formulation of impedance boundary conditions
for a high skin effect in various conducting media.
Chapter 3 presents the theory of regular waveguides with finitely conducting
walls, and Chapter 4 the theory of cavities when the surfaces and the medium
inside are absorbing. These chapters present the derivation of general formulae
for the attenuation coefficient and (^-factor and consider concrete practical
applications. The principal errors associated with the solution of these problems
are also discussed.
Chapters 5 and 6 deal with wave diffraction by imperfectly conducting
gratings in both free space and inhomogeneous anisotropic media. The main
emphasis is on the description of dissipative resonance effects, in particular the
effect of the abnormally low dissipation.
Chapter 7 considers the attenuation of eigenmodes in periodic waveguides. It
presents results obtained for low-loss flexible corrugated waveguides and high-
quality corrugated resonators of the millimetre waveband etc.
A number of theoretical results confirmed by experiment are included.
ix Preface
The book is intended for physicists and engineers performing theoretical
research and designing microwave and millimetre-wave devices, and for students
and postgraduates involved in these issues. It can be used by a design engineer
to select a suitable type of a waveguide (resonator) and methods of computing
its parameters.
As similar problems arise in acoustics, much of the book's material can be
directly used for sound waves; this makes it useful for specialists in acoustics.
The authors are grateful to Prof. E.A. Alkhovsky, Prof. A.A. Kuraev, Prof.
V.A. Cherepenin, Dr. T.N. Galishnikova, Dr. V.V. Zarubanov and
Mrs. V.N. Rodionova who made valuable contributions to the research.
The authors greatly appreciate the support and encouragement given by Prof.
PJ.B. Clarricoats which has enabled the book to be written.