الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
In this thesis, a study for the impact of propagation on antennas for Ground Penetrating Radar (GPR) is done, a novel Ultra-wideband Willis-Sinha Tapered Slot antenna for landmine detection using Ground Penetrating Radar (GPR) system with enhanced gain and directivity is presented. The structure is constructed on FR4 dielectric substrate which is low cost material. The antenna is fed by novel tapered coplanar waveguide (CPW) to coplanar strips (CPS) transition feed. The antenna’s impedance bandwidth is extended by adding an antenna arm constructing parabola shape with the antenna element. The antenna has a corrugated structure along the antenna outer edges to improve radiation efficiency and get higher directivity. Also, mushroom like circular EBG structure is used in the lower side of the antenna arm to reduce interference and enhance front-to-back ratio (F/B ratio). A partially substrate removal like circular cylinders inside the substrate are aligned with the antenna tapered profile to obtain better radiation efficiency and enhance antenna gain.
Secondly, A novel Ultra-wideband CPW to CPS transition for TSA in landmine detection in GPR system is proposed. EBG structures of coplanar circular patches exist near the transition open slot and aligned with the outer edge of the CPW ground. To characterize this transition, the equivalent - circuit model of back-to-back transition that consists of non-uniform transmission lines is established using ABCD parameters by MATLAB program. The design verification is done by comparing the calculated and converted S-parameters and simulated one using FDTD simulation (CST Studio Ver 15). The results based on equivalent-circuit model, FDTD simulation, and measurements are compared and good agreements were found between numerical and experimental results.
Finally, modeling and simulation of the GPR propagation medium using ready-made electromagnetic software packages and MATLAB program have been achieved using stretched coordinates. In addition, the clutter reduction method using appropriate techniques for buried objects detection/imaging has been achieved by MATLAB program which is constructed to do these analyses.