A tapered short helical antenna radiating a circularly polarized tilted beam

摘要

A circularly polarized (CP) wave radiation beam tilted from the direction normal to an antenna plane can be obtained using spiral [1][2] and loop antennas [3]. However, little theoretical analysis for the tilted beam from a helical antenna has been performed. This paper fills this gap and a CP tilted beam is obtained using a tapered short helical antenna. The frequency responses of the axial ratio and gain in the beam direction, together with the input impedance, are calculated and discussed.