Radio Wave Propagation and Parabolic Equation Modeling

Gokhan Apaydin, Levent Sevgi

• Publisher: Wiley-IEEE Press
• Year: 2017
• Print ISBN: 9781119432111
• eBook ISBN: 9781119432159
• Edition: 1
• Topic: Physical Sciences
• Subtopic: Electromagnetism

An important contribution to the literature that introduces powerful new methods for modeling and simulating radio wave propagation

A thorough understanding of electromagnetic wave propagation is fundamental to the development of sophisticated communication and detection technologies. The powerful numerical methods described in this book represent a major step forward in our ability to accurately model electromagnetic wave propagation in order to establish and maintain reliable communication links, to detect targets in radar systems, and to maintain robust mobile phone and broadcasting networks.

The first new book on guided wave propagation modeling and simulation to appear in nearly two decades, Radio Wave Propagation and Parabolic Equation Modeling addresses the fundamentals of electromagnetic wave propagation generally, with a specific focus on radio wave propagation through various media. The authors explore an array of new applications, and detail various virtual electromagnetic tools for solving several frequent electromagnetic propagation problems. All of the methods described are presented within the context of real-world scenarios typifying the differing effects of various environments on radio-wave propagation. This valuable text:

• Addresses groundwave and surface wave propagation
• Explains radar applications in terms of parabolic equation modeling and simulation approaches
• Introduces several simple and sophisticated MATLAB scripts
• Teaches applications that work with a wide range of electromagnetic, acoustic and optical wave propagation modeling
• Presents the material in a quick-reference format ideal for busy researchers and engineers

Radio Wave Propagation and Parabolic Equation Modeling is a critical resource forelectrical, electronics, communication, and computer engineers working on industrial and military applications that rely on the directed propagation of radio waves. It is also a useful reference for advanced engineering students and academic researchers.

CHAPTER 1
INTRODUCTION

1.1 Electromagnetic Problems and Classification

Electromagnetic (EM) problems are classified in terms of the equations describing them. The equations could be differential or integral or both. Most EM problems can be stated in terms of an operator equation

(1.1)

where L is an operator (differential, integral, or integro-differential), g is the known excitation or source, and ϕ is the unknown function to be determined. A typical example is an electrostatic problem involving Poisson's equation

(1.2)

where L = −∇² is Laplacian operator, g = ρ/ϵis source term, and ϕ= V. In integral form, Poisson's equation is of the form

(1.3)

where

is Laplacian operator, g = V is source term, and ϕ = ρ/ϵ.

Electromagnetic problems involve linear, second-order differential equations. In general, a second-order partial differential equation (PDE) is given by

(1.4)

where the differential operator is

(1.5)

The coefficients, a, b, and c, in general are functions of x and y; they may also depend on ϕitself, in which case the PDE is said to be nonlinear. A PDE in which g(x, y) equals zero is termed homogeneous; it is inhomogeneous if g(x, y) is not equal to zero.

A PDE, in general, can have both boundary values and initial values. PDEs whose boundary conditions (BCs) are specified are called steady-state equations. If only initial values are specified, they are called transient equations.

Any linear second-order PDE can be classified as elliptic, hyperbolic, or parabolic depending on the coefficients a, b, and c. The terms hyperbolic, parabolic, and elliptic are derived from the fact that the quadratic equation

(1.6)

represents a hyperbola, parabola, or ellipse if b² — Aac is positive, zero, or negative, respectively.

In each of these categories, there are PDEs that model certain physical phenomena. Such phenomena are not limited to electromagnetics but extend to almost all areas of science and engineering. Thus the mathematical model specified here arises in problems involving heat transfer, boundary-layer flow, vibrations, elasticity, electrostatic, wave propagation, and so on.

Elliptic PDEs are associated with steady-state phenomena, that is boundary-value problems. Typical examples of this type of PDE include Laplace's equation

(1.7)

and Poisson's equation

(1.8)

where in both cases a = c = l,b = 0. An elliptic PDE usually models an interior problem, and hence the solution region...

Table of contents

• COVER
• IEEE EDITORIAL BOARD
• TITLE PAGE
• Copyright
• PREFACE
• ACRONYMS
• MATLAB CODES
• CHAPTER 1: INTRODUCTION
• CHAPTER 2: WAVE PROPAGATION OVER FLAT EARTH
• CHAPTER 3: PARABOLIC EQUATION MODELING
• CHAPTER 4: WAVE PROPAGATION AT SHORT RANGES
• CHAPTER 5: PE AND TERRAIN MODELING
• CHAPTER 6: ANALYTICAL EXACT AND APPROXIMATE MODELS
• CHAPTER 7: WAVE PROPAGATION INSIDE THREE-DIMENSIONAL RECTANGULAR WAVEGUIDE
• CHAPTER 8: TWO-WAY PE MODELS
• CHAPTER 9: PETOOL VIRTUAL PROPAGATION PACKAGE
• CHAPTER 10: FEMIX VIRTUAL PROPAGATION PACKAGE
• REFERENCES
• INDEX
• EULA