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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
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.
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