الفهرس 
Chapter 1: IntroductionOnly 14 pages are availabe for public view
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Abstract
Nanotechnology antenna and optoelectronic devices Due to the ability of nanotechnology to produce new materials with amazing
properties, it is now extensively researched for application in many fields.
This thesis examines the use of some nanomaterials for optoelectronic
devices and antenna applications. Three kinds of materials are
investigated, namely carbon nanotubes (CNTs), nanocomposites and
quantum dots (QDs).Nanotechnology antenna and optoelectronic devices
Due to the ability of nanotechnology to produce new materials with amazing
properties, it is now extensively researched for application in many fields.
This thesis examines the use of some nanomaterials for optoelectronic
devices and antenna applications. Three kinds of materials are
investigated, namely carbon nanotubes (CNTs), nanocomposites and
quantum dots (QDs).
The use of some nanocomposites in place of substrate and metallic parts of
microstrip antenna (MSA), as an example of using materials based on
nanotechnology in RF antenna, is investigated. HFSS is used to design and
analyze an S shape MSA for wireless communication systems covering 5-6
GHz frequency band. The substrate used in this design is BST-ER140
composite with nanosilver additives. The nanocomposite substrate with high
dielectric constant which has been used results in very small antenna size. The
use of conductive nanocomposites is investigated for building antennas, by
replacing the metal with different conductive nanocomposites such as RCCF/MWCNT, buckypaper and conductive ink. The effect of conductivity
and thickness of each material on antenna performance is investigated.
Also, HFSS is used to design and simulate a microstrip antenna based on
nanocomposite materials to operate at 2.4/3.5 GHz, 2.4 GHz band used for
Bluetooth and WIFI applications while 3.5 GHz band used for WIMAX. 3.5
GHz band is chosen in our design because it is allocated in most countries for
Fixed Wireless and/or Satellite.
CNTs are researched for antenna applications; it is found that it, single CNT or
bundle, can be used as a dipole antenna at THz frequencies. Also, through this
thesis we study the characteristics of multiwall CNT (MWCNT) as an opticalantenna. CST is used to simulate MWCNT as a nanorode antenna. The
dependence of the MWCNT antenna parameters on its dimensions is studied.
Also, the characteristics of coupled MWCNTS and MWCNT array are
considered.
As an application of using nanomaterials in optoelectronic devices, CdTe QDs
are used as an emissive layer for organic light emitting device (OLED). The
excellent size dependent, bright and narrow photoemission of colloidal
semiconductor cadmium nanocrystals, make them attractive materials for
OLED. Two detailed design method for microcavity QD-OLED are introduced
through this thesis. Three QD-OLEDs for blue, green and red emissions are
designed and simulated. The effect of the device geometry on the light intensity
is investigated and the devices are optimized for maximum intensity.