الفهرس 
Chapter (1): Introduction.Only 14 pages are availabe for public view
 |  | from | 87 |  |  |
| | | from | 87 | | |
Abstract
In this thesis a planar patch antenna for mobile communication
applications operating at 1.8, 3.5, and 5.4 GHz, is proposed. A planar
microstrip patch antenna (MPA) consists of two F-shaped resonators that
enable operations at 1.8 and 3.5 GHz, while operation at 5.4 GHz is
achieved when the patch is truncated from the middle. The proposed
planar patch is printed on a low-cost FR-4(𝜀𝑟=4.3) substrate that is 1.6
mm in thickness. We obtained a good agreement between simulation and
measurement results. The proposed antenna has an elliptically shaped
radiation pattern at 1.8 and 3.5 GHz, while the broadside directional
pattern is obtained at the 5.4 GHz frequency band. At 1.8, 3.5, and 5.4
GHz, the simulated peak realized gains of 2.34, 5.2, and 1.42 dB are
obtained and compared to the experimental peak realized gains of 2.22,
5.18, and 1.38, dB at the same frequencies. The results indicate that the
proposed planar patch antenna can be utilized for mobile applications
such as digital cellular systems (DCS), worldwide interoperability for
microwave access (WiMAX), and wireless local area networks (WLAN).
A new reconfigurable antenna is presented. The Reconfigurability is
obtained by inserting avaractor diode in a small rectangular cut in the
patch. The technique is implemented using two lumped variable
capacitors (Varactor diode), and adding two parasitic patches connected
at the corners of the microstrip patch antenna. These works provide
various operating frequencies; the frequency range from 1.52 to 2.55
GHz, from 3.3 to 3.55 GHz, and 5.15 GHz. There are many practical
applications such as GSM, Gps, WLAN, WIMAX, etc. The
reconfigurable antenna changes the application according to a change in
the capacitance of the Varactor diode. CST software was used for the
simulation.