Wideband dual-sense circularly polarization helical antenna with axial dual-beam operation

Abstract

A wideband dual-sense circularly polarization helical antenna with axial dual-beam operation mode is proposed in this paper. The proposed antenna is composed of two-arm helical wires with opposite sense of rotation, which produces left-hand circularly polarization (LHCP) wave and right-hand circularly polarization (RHCP) wave from each helical arm respectively. By adjusting the geometry parameters of the helical wire, the axial dual-beam radiation is realized. The antenna, fed at the center of these two helical wires with seven turns, is simulated, and good performance is achieved. In the frequency range from 1.7 GHz to 3.05 GHz, the gain of LHCP and RHCP is about 8 dBi, along with axial ratio below 3 dB in beam-width from 30 to 120 degrees. The cross polarization is lower than −20 dB in both two boresight directions at 2.8 GHz.