A Single-fed Circularly-Polarized UHF Yagi-Uda Antenna

In this paper, a wide band circularly polarized Yagi-Uda antenna is proposed. The design consists of two orthogonal linear polarized Yagi antennas and two coupling rods The main advantage of this design is that it not only has a very high gain but also realize circular polarization, thus it could be an excellent candidate for satellite communication. To verify the proposed design, both simulations and measurements are conducted. The results show that the antenna realize a S11 < -10 dB bandwidth 360 MHz to 454 and an axial ratio (AR) < 3 dB bandwidth from 374 MHz to 424 MHz, with a maximum gain of 9.3 dBi.