Main-beam polarization properties of modified helical antennas

The polarization properties of modified helical antennas are investigated for a wide range of directions using a two-dimensional polarization diagram. The current distribution on the antenna and the radiated field are calculated for several variations of the antenna shape to show the influences of the helix design on the main-beam polarization characteristics. This extended knowledge about typical polarization diagrams yields conditions for the antenna design. Special emphasis is placed on the choice of the geometrical parameters for the open end and the feed region of the antenna to meet different system requirements. The calculated results are confirmed with measured polarization characteristics and radiation patterns for experimental helices.<
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