الفهرس 
CHAPTER ONE: INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
This thesis addresses analysis and design of high gain transmitarray lens
antennas which can be used in satellite communication, radar application system,
imaging, and medical applications. Different types of transmitarray antennas are
proposed. A new design of transmitarray from one dielectric sheet with etchings of
different heights is discussed. A single structure multi-focused transmitarray in the nearfield
(NF) and/or far-field (FF) is designed by using a chess-board arrangement of unitcell
elements. Multi-focused transmitarray antennas for FF/FF, FF/NF, and NF/NF are
investigated. Reflectarrays / transmitarrays of a transparent hemispherical dielectric
resonator antenna integrated with solar cells for small satellite and clean energy are
proposed. Integration between these antennas and solar cells serves as a cover protection
for the solar cell from environment which increases the efficiency of solar cells. A
design of compact multi-function graphene lens antenna in terahertz (THz) band is also
proposed. Tunability of graphene conductivity introduces multi-function characteristics
of a single array structure in the THz band. A new design of folded transmitarray which
gives a good radiation characteristics and decreases the depth of the antenna is also
presented. The effect of the NF-focused folded transmitarray on human knee is also
investigated. This technique can be used to focus electromagnetic energy for the
purpose of thermal therapy. Circular polarized folded transmitarray is also studied.
Ability of enhanced polarization diversity by electrically controlling the biasing of the
two PIN diodes is proposed. Three types of the polarizations are presented, left hand
circular polarized (LHCP), right hand circular polarized (RHCP), and linear polarized
(LP).