الفهرس 
CHAPTER 1: IntroductionOnly 14 pages are availabe for public view
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Abstract
This thesis addresses Nano-antennas that have a relatively wide bandwidth and is suitable for fast data communications. The properties of metals in the THz range have been investigated using the Drude model. The radiation characteristics of nano-dielectric resonator antenna (NDRA) reflectarray at 633 nm have been examined. A parametric study for the NDRA unit cell dimensions and material has been carried out. Different types of metals are used as a supporting plane of the NDRA unit-cell. NDRAs with silver, copper, and aluminum supporting plane have been designed and analyzed for reflectarray and transmitarray antennas. A nano-reflectarray/transmitarray unit-cells with supporting plane that have been made from different metals have been explored. A comparison between the radiation characteristics of 17×17 and 21×21 cell elements NDRA transmitarray with silver supporting plane has been presented. Different supporting plane metals have been examined. A compromise between the size, maximum gain, and operating bandwidth of nano-transmitarray is worked out for THz applications. The finite integral technique is used to carry a full wave analysis to design a NDRA reflectarray and a NDRA transmitarray. Design of 411 unit-cells in a circular configuration transmitarray using dielectric resonator antenna (DRA) has been carried out. The proposed transmitarray is used as a terahertz (THz) antenna at 4.5 THz, enabling wireless network on-chip interconnections for multi-core processor technology. Linearly polarized single-beam and multi-beam transmitarrays fed by linearly polarized horn have been designed and investigated. New proposed transmitarray layout arrangement for multi-beam configuration allows the distribution of the elements over the whole array aperture, which allowed higher gain for each beam. A 2×2 circularly polarized DRA sub-array is used to feed the transmitarray instead of the horn for circular polarization. This is for more the compactness and easier integration with the array. Circularly polarized transmitarray fed by the DRA sub-array have been investigated for single-beam and triple-beam applications. Triple-beam directive transmitarray antenna has been designed for beams at angles +30o, 0o, and -30o. The cells for such antenna has been arranged by using successive cells for +30o, 0o, and 30o triple-beam transmitarray. A folded transmitarray is used to reduce the size of the transmitarray antenna by using a folding metal plate located at distance from the array aperture. A linearly-polarized receiving mode nanoantenna is designed for solar energy harvesting. The infrared nanoantenna is used to collect the solar radiation and converting it to electric energy. The proposed nanoantenna is a thin dipole made of gold and printed on a silicon dioxide substrate. The two side conductors of the dipole have been shaped in a rhombus form. The nanoantenna dipole is able to focus the electromagnetic energy into small localized area at the tips of the two side conductors on the dipole feeding gap. Therefore, a maximum (focused) near field intensity across the gap is achieved. The dimensions of the dipole are optimized for maximum near electric field intensity at a frequency of 28.3 THz. A metal insulator metal (MIM) diode is integrated with the nanoantenna to rectify the received energy. A dual-polarized, four side-arms, rhombus shaped nanoantenna dipole for energy harvesting has been designed and optimized for 28.3 THz applications.