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This new handbook on radar signal analysis adopts a deliberate and
systematic approach. It uses a clear and consistent level of
delivery while maintaining strong and easy-to-follow mathematical
details. The emphasis of this book is on radar signal types and
their relevant signal processing and not on radar systems hardware
or components. This handbook serves as a valuable reference to a
wide range of audience. More specifically, college-level students,
practicing radar engineers, as well as casual readers of the
subject are the intended target audience of the first few chapters
of this book. As the book chapters progress, these grow in
complexity and specificity. Accordingly, later chapters are
intended for practicing engineers, graduate college students, and
advanced readers. Finally, the last few chapters contain several
special topics on radar systems that are both educational and
scientifically entertaining to all readers. The presentation of
topics in this handbook takes the reader on a scientific journey
whose major landmarks comprise the different radar subsystems and
components. In this context, the chapters follow the radar signal
along this journey from its birth to the end of its life. Along the
way, the different relevant radar subsystems are analyzed and
discussed in great detail. The chapter contributors of this new
handbook comprise experienced academia members and practicing radar
engineers. Their combined years of academic and real-world
experiences are in excess of 175. Together, they bring a unique,
easy-to-follow mix of mathematical and practical presentations of
the topics discussed in this book. See the "Chapter Contributors"
section to learn more about these individuals.
In recent years, transmitarray antennas have attracted growing
interest with many antenna researchers. Transmitarrays combines
both optical and antenna array theory, leading to a low profile
design with high gain, high radiation efficiency, and versatile
radiation performance for many wireless communication systems. In
this book, comprehensive analysis, new methodologies, and novel
designs of transmitarray antennas are presented. Detailed analysis
for the design of planar space-fed array antennas is presented. The
basics of aperture field distribution and the analysis of the array
elements are described. The radiation performances (directivity and
gain) are discussed using array theory approach, and the impacts of
element phase errors are demonstrated. The performance of
transmitarray design using multilayer frequency selective surfaces
(M-FSS) approach is carefully studied, and the transmission phase
limit which are generally independent from the selection of a
specific element shape is revealed. The maximum transmission phase
range is determined based on the number of layers, substrate
permittivity, and the separations between layers. In order to
reduce the transmitarray design complexity and cost, three
different methods have been investigated. As a result, one design
is performed using quad-layer cross-slot elements with no
dielectric material and another using triple-layer spiral dipole
elements. Both designs were fabricated and tested at X-Band for
deep space communications. Furthermore, the radiation pattern
characteristics were studied under different feed polarization
conditions and oblique angles of incident field from the feed. New
design methodologies are proposed to improve the bandwidth of
transmitarray antennas through the control of the transmission
phase range of the elements. These design techniques are validated
through the fabrication and testing of two quad-layer transmitarray
antennas at Ku-band. A single-feed quad-beam transmitarray antenna
with 50 degrees elevation separation between the beams is
investigated, designed, fabricated, and tested at Ku-band. In
summary, various challenges in the analysis and design of
transmitarray antennas are addressed in this book. New
methodologies to improve the bandwidth of transmitarray antennas
have been demonstrated. Several prototypes have been fabricated and
tested, demonstrating the desirable features and potential new
applications of transmitarray antennas.
In this work, an iterative approach using the finite difference
frequency domain method is presented to solve the problem of
scattering from large-scale electromagnetic structures. The idea of
the proposed iterative approach is to divide one computational
domain into smaller subregions and solve each subregion separately.
Then the subregion solutions are combined iteratively to obtain a
solution for the complete domain. As a result, a considerable
reduction in the computation time and memory is achieved. This
procedure is referred to as the iterative multiregion (IMR)
technique. Different enhancement procedures are investigated and
introduced toward the construction of this technique. These
procedures are the following: 1) a hybrid technique combining the
IMR technique and a method of moment technique is found to be
efficient in producing accurate results with a remarkable computer
memory saving; 2) the IMR technique is implemented on a parallel
platform that led to a tremendous computational time saving; 3)
together, the multigrid technique and the incomplete lower and
upper preconditioner are used with the IMR technique to speed up
the convergence rate of the final solution, which reduces the total
computational time. Thus, the proposed iterative technique, in
conjunction with the enhancement procedures, introduces a novel
approach to solving large open-boundary electromagnetic problems
including unconnected objects in an efficient and robust way.
Contents: Basics of the FDFD Method / IMR Technique for Large-Scale
Electromagnetic Scattering Problems: 3D Case / IMR Technique for
Large-Scale Electromagnetic Scattering Problems: 2D Case / The IMR
Algorithm Using a Hybrid FDFD and Method of Moments Technique /
Parallelization of the Iterative Multiregion Technique / Combined
Multigrid Technique and IMR Algorithm / Concluding Remarks /
Appendices
This book presents a new global optimization technique using
Taguchi's method and its applications in electromagnetics and
antenna engineering. Compared with traditional optimization
techniques, Taguchi's optimization method is easy to implement and
very efficient in reaching optimum solutions. Taguchi's
optimization method is developed based on the orthogonal array (OA)
concept, which offers a systematic and efficient way to select
design parameters. The book illustrates the basic implementation
procedure of Taguchi's optimization method and discusses various
advanced techniques for performance improvement. In addition, the
integration of Taguchi's optimization method with commercial
electromagnetics software is introduced in the book. The proposed
optimization method is used in various linear antenna arrays,
microstrip filters, and ultra-wideband antenna designs. Successful
examples include linear antenna array with a null controlled
pattern, linear antenna array with a sector beam, linear antenna
array with reduced side lobe levels, microstrip band stop filter,
microstrip band pass filter, coplanar waveguide band stop filter,
coplanar ultra-wide band antenna, and ultra-wide band antenna with
band notch feature. Satisfactory results obtained from the design
process demonstrate the validity and efficiency of the proposed
Taguchi's optimization method. Contents: Introduction / Orthagonal
Arrays / Taguchi's Optimization Method / Linear Antenna Array
Designs / Planar Filter Designs / Ultra-wide Band (UWB) Antenna
Designs / OA-PSO Method / Conclusions
This book introduces the powerful Finite-Difference Time-Domain
method to students and interested researchers and readers. An
effective introduction is accomplished using a step-by-step process
that builds competence and confidence in developing complete
working codes for the design and analysis of various antennas and
microwave devices. This book will serve graduate students,
researchers, and those in industry and government who are using
other electromagnetics tools and methods for the sake of performing
independent numerical confirmation. No previous experience with
finite-difference methods is assumed of readers. Key features
Presents the fundamental techniques of the FDTD method at a
graduate level, taking readers from conceptual understanding to
actual program development. Full derivations are provided for final
equations. Includes 3D illustrations to aid in visualization of
field components and fully functional MATLAB (R) code examples.
Completely revised and updated for this second edition, including
expansion into advanced techniques such as total field/scattered
field formulation, dispersive material modeling, analysis of
periodic structures, non-uniform grid, and graphics processing unit
acceleration of finite-difference time-domain method.
The objective of this book is to introduce students and interested
researchers to antenna design and analysis using the popular
commercial electromagnetic software FEKO. This book, being tutorial
in nature, is primarily intended for students working in the field
of antenna analysis and design; however the wealth of hands-on
design examples presented in this book along with simulation
details, makes it a valuable reference for practicing engineers.
The requirement for the readers of this book is to be familiar with
the basics of antenna theory; however electrical engineering
students taking an introductory course in antenna engineering can
also benefit from this book as a supplementary text. The key
strengths of this book are as follows: First, the basics of antenna
simulation will be presented in a detailed, understandable, and
easy to follow procedure through study of the simplest types of
radiators, i.e. dipole and loop antennas, in chapters 2 and 3. This
will build the fundamental knowledge a student would need in order
to utilize antenna simulation software in general. Second,
comparison between theoretical analysis and full-wave simulation
results of FEKO are given for a variety of antenna types, which
will aid the readers with a better understanding of the theory,
approximations and limitations in the theoretical analysis, and
solution accuracy. Third, and of paramount importance, is the
visualization of the antenna current distribution, radiation
patterns, and other radiation characteristics that are made
available through full-wave simulations using FEKO. A proper
analysis of the radiation characteristics through these
visualizations serves as a powerful educational tool to fully
understand the radiation behaviour of antennas
This book presents the theory of adjoint sensitivity analysis for
high frequency applications through time-domain electromagnetic
simulations in MATLAB (R). This theory enables the efficient
estimation of the sensitivities of an arbitrary response with
respect to all parameters in the considered problem. These
sensitivities are required in many applications including
gradient-based optimization, surrogate-based modeling, statistical
analysis, and yield analysis. Using the popular FDTD method, the
book shows how wideband sensitivities can be efficiently estimated
for different types of materials and structures, and includes
plenty of well explained MATLAB (R) examples to help readers absorb
the content more easily and to make the theory more understandable
to the broadest possible audience. Topics covered include a review
of FDTD and an introduction to adjoint sensitivity analysis; the
adjoint variable method for frequency-independent constitutive
parameters; sensitivity analysis for frequency-dependent objective
functions; transient adjoint sensitivity analysis; adjoint
sensitivity analysis with dispersive materials; adjoint sensitivity
analysis of anisotropic structures; nonlinear adjoint sensitivity
analysis; second-order adjoint sensitivities; and advanced topics.
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