Design and construction of reduced size planar spiral antenna in the 0.5-18 ghz frequency range

Yıldız, İnanç
In this thesis, theoretical and practical evaluation of usual spiral antenna is revised. Working principles of both types of planar spiral antennas as Equiangular and Archimedean are introduced. A predesigned microstrip tapered balun used for feeding section of a spiral antenna is simulated on Ansoft HFSS software. Successful simulation results are obtained and measurements of implemented balun structure are made by using an HP 8722 D vector network analyzer. Antenna measurement techniques used in this study are introduced. Measurement set-ups are defined and some preliminary knowledge is given on these. As the main matter of thesis, reduced size planar spiral antennas are designed and implemented. Return loss, gain; radiation and polarization patterns of antennas are measured. Datasets of measurements are compared with each other and with reference spiral antenna. Quite promising results are obtained and size reduction of spiral antenna is achieved in many aspects.


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Citation Formats
İ. Yıldız, “Design and construction of reduced size planar spiral antenna in the 0.5-18 ghz frequency range,” M.S. - Master of Science, Middle East Technical University, 2004.