Charge acceleration and the spatial distribution of radiation emitted by antennas and scatterers.

Format:

Book

Author/Creator:

Miller, Edmund K.

Series:

Electromagnetic Waves Series

Language:

English

Subjects (All):

Electromagnetic waves.

Physical Description:

1 online resource (217 pages)

Edition:

1st ed.

Place of Publication:

Paris : Institution of Engineering & Technology, 2023.

Summary:

The book focuses on various aspects of EM radiation from a variety of perspectives. The goal is to provide the reader with a conceptual basis for understanding EM radiation and to introduce some associated computational tools for obtaining relevant quantitative results relating to its distribution.

Contents:

Intro

Title

Copyright

Contents

Journal articles and book chapters that are related to electromagnetic radiation by the author and his colleagues

About the author

Dedication

Presentations

Preface

Introduction

1 Overview

1.1 Introduction

1.2 The electric-field kink model of electromagnetic radiation

1.3 The proportionality between charge acceleration and radiation from a generic wire object

1.4 Time-domain energy measures

1.5 The dependence of time-domain radiation loss on the circumference and wire radius of a circular loop

1.6 The differentiated on-surface Poynting vector as a measure of radiation loss from wires

1.7 Time-domain far-field analysis of radiation sources (TDFARS) and TWTD

1.8 Frequency-domain far-field analysis of radiation sources (FDFARS) and NEC

1.9 A comparison of time-domain and frequency-domain FARS

1.10 An examination of the radiation properties of specified currents

1.11 Development and comparison of the incremental FARS (IFARS) and incremental IEMF (IIEMF) methods

1.12 The Schelkunoff-Feldman radiation resistance

1.13 Comparison of the radiation properties of a sinusoidal current filament and a PEC dipole of near-zero radius

1.14 The incremental FAR field and degrees of freedom of the sinusoidal current filament

1.15 Appendix A

1.16 Appendix B

References

2 The electric-field kink model of electromagnetic radiation

2.1 Introduction

2.1.1 The propagation speed of EM fields is finite

2.1.2 Electric lines of force are continuous

2.2 The "KINK" model of radiation

2.3 Some simple charge motions that produce radiation

2.3.1 An abrupt start and stop

2.3.2 A charge abruptly stopped

2.3.3 A charge given a constant push

2.3.4 A charge moving at constant speed around a circle.

2.3.5 A charge moving at constant speed around a square

2.3.6 A charge undergoing oscillatory motion

2.3.7 The effect of increasing speed on an oscillating charge

2.4 How field lines close on a physical antenna

2.5 Summary

3 Charge-acceleration and radiation from a generic wire object

3.1 Introduction

3.2 Charge reflection and radiation

3.3 A preview of radiation and current decay for a straight wire

3.4 Comparing current decay on a long wire and circular loop

3.5 Source-region radiation

3.6 Propagation radiation

3.7 Reflection radiation from the end of a wire

3.8 Reflection radiation from resistive loads

3.9 Radiation from directional reflection at a 90-deg bend

3.10 Reflection radiation from a step in the wire radius

3.11 An energy measure that demonstrates radiation loss

3.12 Summary of the derived AFs

3.13 Summary

4 Time-domain electromagnetic-field energy measures

4.1 Introduction

4.2 Stored-energy measures

4.3 Implementation of time-domain energy measures

4.4 Some additional examples of TDEMs

4.5 Summary

5 Radiation-loss dependence of a circular loop antenna on its circumference and wire radius

5.1 Introduction

5.2 Numerical results for the loop antenna

5.2.1 Varying the loop circumference

5.2.2 Varying the loop wire radius

5.3 Comparing a loop and straight wire

5.4 Summary

6 Differentiating the on-surface Poynting vector of a wire to determine its radiation loss

6.1 Introduction: current decay and propagation radiation in the frequency domain

6.1.1 Current decay and charge reflection in the frequency domain

6.2 A preview of frequency-domain FARS

6.3 Power flow near a straight-wire antenna

6.3.1 The PV

6.3.2 Power flow near a PEC wire.

6.4 FARS and differentiated-PV (DPV) results for a dipole antenna

6.5 FARS and DPV results for a transmission-line driven dipole antenna

6.6 FARS and DPV results for a straight-wire scatterer

6.6.1 FARS and the DPV

6.6.2 FARS and the DPV for a 10-wavelength scatterer at near-axial incidence

6.6.3 The near-interaction field on a straight-wire scatterer

6.7 FARS and DPV results for some other thin-wire antennas

6.7.1 A dipole with two right-angle bends

6.7.2 A circular loop antenna

6.7.3 A square loop antenna

6.7.4 A zigzag antenna

6.8 Summary

Acknowledgment

7 Time-domain far-field analysis of radiation sources and TWTD

7.1 Introduction

7.1.1 The perfect electric conductor as a radiator

7.1.2 Why does radiation occur?

7.1.3 Charge acceleration on a perfect electric conductor excited as an antenna

7.2 Time-domain FARS (TDFARS)

7.3 Validating time-domain FARS

7.4 Some representative applications of TDFARS

7.4.1 Radiation from straight wires

7.4.2 Scattering from straight wires

7.4.3 Radiation from loops

7.5 The effect of varying the source location

7.6 How charge reflection causes the FARS energy distribution

7.7 Summary

Appendix A: The occurrence of negative linear-power and -energy results from FARS

8 Frequency-domain far-field analysis of radiation sources and NEC

8.1 Introduction

8.2 Some background

8.3 The FARS approach

8.4 The induced electromotive force method

8.5 Tangential electric fields of the sinusoidal current filament

8.6 Initial FDFARS results for the sinusoidal current filament

8.7 FDFARS results for straight wires

8.8 FDFARS results for wire loops

8.9 FDFARS results for arrays

8.10 Other geometries

8.11 A more complex geometry

8.12 Summary

References.

9 Time-domain FARS and frequency-domain FARS compared

9.1 Comparison of time-domain and frequency-domain far-field analysis of radiation sources

9.2 Results for straight wires

9.3 Results for wire loops

9.4 The transmission-line excited dipole antenna

9.5 A dipole enclosed by a wire cage

9.6 Summary

10 The radiation properties of some specified currents

10.1 Introduction

10.2 Using the IEMF method to analyze radiation from the SCF

10.3 Results for other specified currents

10.4 The Schelkunoff-Feldman distributed radiation resistance

10.5 Summary

11 The incremental FARS (IFARS) and incremental IEMF (IIEMF) methods

11.1 Some background

11.2 Generalizing the IEMF method

11.3 FARS and its incremental version

11.3.1 The basic frequency-domain FARS

11.3.2 Incremental FARS

11.4 The incremental IEMF method

11.5 Numerical results

11.6 Discussion

11.7 Summary

12 The Schelkunoff-Feldman radiation resistance

12.1 Discussion and extension

12.2 Summary

13 Radiation from a near-zero-radius dipole and a sinusoidal current filament

13.1 Introduction

13.2 Ways in which the SCF and PEC dipole are similar

13.2.1 Total radiated power as a function of current length

13.2.2 Radiation pattern

13.2.3 Linear power density

13.2.4 Schelkunoff-Feldman distributed radiation resistance

13.3 Ways in which the SCF and PEC dipole are different

13.3.1 Current distributions

13.3.2 Time-average Poynting vectors parallel to the currents

13.3.3 Tangential electric fields

13.3.4 Distributions of induced EMF power

13.4 The different radiation mechanisms for the near-zero-radius dipole and the sinusoidal current filament

13.4.1 Radiation from the sinusoidal current filament

13.4.2 Radiation from the PEC dipole

13.5 Summary.

References

14 The pattern rank and spatial radiation distribution of radiation emitted by a sinusoidal current filament

14.1 Introduction

14.2 The far field of the SCF

14.3 The implications of numerically evaluating the far field

14.4 Examination of the far-field analytical expression

14.5 Examination of numerically evaluating the far field

14.6 The degrees of freedom of various patterns

14.7 Current and charge relationship to radiation

14.8 Summary

Appendix A The thin-wire time-domain (TWTD) computer code

Appendix B The Numerical Electromagnetics Code (NEC)

Appendix C Notation

Index.

Notes:

Description based on publisher supplied metadata and other sources.

Other Format:

Print version: Miller, Edmund K. Charge Acceleration and the Spatial Distribution of Radiation Emitted by Antennas and Scatterers

ISBN:

9781523155385

1523155388

9781839538148

1839538147

OCLC:

1374426734