Improving operational performance of antennas on complex platforms by arranging their placements

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2010
Bayseferoğulları, Can
The aim of this thesis is to improve the operational performance of the communication antennas mounted on complex platforms such as aircrafts and warships by arranging placements of these antennas. Towards this aim, primarily, in order to gain insight on the influence of geometrically simple structures composing the platform on antenna performance, a quarter wavelength monopole antenna placed at the center of a finite square ground plane is studied by using uniform Geometrical Theory of Diffraction (GTD). Besides, the change of far field radiation pattern and complex diffraction functions due to the variation of the width of a square ground plane is examined. Secondly, electromagnetic analysis of two Ultra High Frequency (UHF) antennas mounted on geometrically simple structures composing simplified F-4 aircraft is carried out by using transient solver of Computer Simulation Technology (CST) Microwave Studio® (MWS), in order to conceive the influence of each structure on antenna performance. Then, electromagnetic analysis of these antennas mounted on simplified and original F-4 aircrafts is performed, in order to determine the optimal location of the lower UHF antenna (newly installed antenna) for the operational performance of this antenna to be optimum in terms of electromagnetic coupling and far field radiation pattern. Finally, electromagnetic analysis of the communication antennas mounted on a warship is performed by using transient solver of CST MWS®, in order to determine the optimal locations of these antennas for the operational performance of these antennas to be optimum in terms of electromagnetic coupling and far field radiation pattern.

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Citation Formats
C. Bayseferoğulları, “Improving operational performance of antennas on complex platforms by arranging their placements,” M.S. - Master of Science, Middle East Technical University, 2010.