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Abstract
The characteristics of new enhanced perfonnance microstrip patch antennas have been designed and analyzed using fuB wave techniques. The MoM and FEM methods as main tools for solving microstrip antennas have been studied in addition to FDTD method. Different new high gain multiband and wideband microstrip patch antennas with complex structures are presented, which are designed and analyzed using a fuB wave analysis simulator. These various patches are entitled, tapered I-beam, rooftile and mazy rooftile, C-shaped and coupled C-shaped, rounded comers dashed rectangular spiral and inverted trapezoid fed by uneven I-beam microstrip patch antennas, which offer exceBent electrical perfonnance and aBow multiband and/or wideband operating frequencies with percentage bandwidth near to 70 % and gain up to 44.8 dB.
The ultra wideband (UWB) is a new radio technology that promises to revolutionize high¬speed data transfers and enable the personal area networking industry leading to new innovations and greater quality of services to the end user. Therefore, two new design patches of ultra wideband wheel and like fractal microstrip patch antennas using non¬unifonn photonic bandgap (PSG) substrate structure are analyzed. These PSGs enhance some modes and weaken others, which have been used to control the antenna bandwidths These patches posses UWB approximately in the range of I GHz to 20 GHz and wideband or multiband above 20 GHz. Finally, UWB planar microstrip array antenna has been presented as an application in radar systems, which provides high performance detection of all modem threats, including theater ballistic missiles up to 0.0000 I m2 and high gain up to 31.4 dB depend on the operating frequency where its range from 2 GHz to 12 GHz. The radiation characteristics for the new high gain, multiband, wideband and UWB designed microstrip patch antennas that were introduced such as return loss, input impedance, voltage standing wave ratio, current distribution, near field, gain, E-plane radiation patterns and 3D-polar radiation patterns have been presented in order to demonstrate the microstrip antenna and array performance.
The advantages and benefits of using frequency ranges that the proposed antennas designed in this thesis operated are illustrated from its low cost, flexibility, ease of installation and reconfiguration, frequency band available, frequency re-use. ease of maintenance and planning restrictions. Also, they offer benefits including; unlicensed operation, highly secure operation, virtually interference-free operation, high level of frequency re-use enabled, fiber optic data . transmission speeds possible, mature technology, carrier-class communication links enabled. The proposed antennas that have been presented can be utilized in variety of applications, such as infrastructures for new mobile radio services (e.g. GSM and DeS 1800), closures/spurs of SDH (Synchronous Digital Hierarchy) rings, extensions of LAN, protection of cable connections, temporary links, high-speed Internet, data, and voice communications, WPAN (Wireless Personal Area Networking), low power sensor networks, wall imaging and through-wall imaging systems or intrusion protection and military applications such as ground penetrating radar and other radars, which have been used to locate enemy objects behind walls and around corners in the battlefield.
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