Novel method for measuring the axial ratio of circularly polarized antennas based on the cross-polarization

In the article, a novel method based on the cross-polarization principles for measuring the axial ratio of circularly polarized antennas is proposed. An auxiliary antenna can work in the left hand circular polarization (LHCP) or the right hand circular polarization (RHCP) through controlling the polarizer connected with this antenna. By measuring received signals of the circularly polarized antenna under test when the auxiliary antenna work in the LHCP or RHCP modes at two different angles, the axial ratio of the antenna under test can be determined. A typical circularly polarized antenna is measured in the anechoic chamber by using this method. Through the comparison between the measured result and the simulation result, the validity of this method is demonstrated. This method enhances the measuring efficiency and has important engineering applications.