الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The technology of locating and positioning objects using wireless satellite communications has grown, significantly, over the last few decades. This technology is a double- edged weapon as it may serve both helpful and harmful purposes depending on how it is utilized. For example, using commercial GPS applications on smartphones can help you to find your way from point A to point B. However, using GNSS to guide a UAV to spy on, attack and/or damage vital targets is considered harmful usage. Therefore, to protect key targets and/or locations against these lethal attacks, anti-attacking systems are in crucial demand.
An anti-attacking system is a wireless jamming system which is meant to radiate a high jamming power around or in a specific direction towards the attacking UAV nearby the protected target. This high jamming power interferes with the navigation aids loaded on the attacking UAV in order to worsen their signal-to-jamming ratio and force the UAV to lose its trajectory or even collapse. This noise power is radiated towards the hostile UAV using a special kind of antenna.
Previous researchers have drawn several designs for such antennas. However, several points have not been fully considered, such as Not all GNSS bands being covered simultaneously, the spatial coverage of the anti-attacking systems being limited due to the limitations of the radiation patterns of the utilized antennas, the limited power handling capability of the used antennas, and the lightness and compactness of the utilized antennas, which determine the mobility of the jamming system.
So, this thesis proposes two implemented antenna designs for two different types of jamming systems; an omnidirectional antenna which is used to protect an entire spherical area against attackers from unknown directions over a short range and a directive antenna which is used to counter-attack UAVs from known directions over a long range. Both designs offer RHCP across the entire band of GNSS. They also have small sizes, light weights, simple manufacture, and low costs in comparison to their counterparts.