Design and Implementation of a X-band Dual-polarization Phased-array Antenna

Abstract

The paper proposes a X-band dual-polarization phased-array antenna based on the vivaldi antenna. As known, the traditional correlation interferometer direction finding system cannot accurately determine the direction of the direct wave, when the wave is mixed with the reflected signals. As an important part of this system, the antenna is improved to solve this problem. The phased-array antenna consists of two sets of $6\times 6$ array antennas, seventy-two phase shifters, fourteen power dividers and a switch circuit. Each $6\times 6$ array antennas is composed of thirty-six vivaldi antennas. The two sets of $6\times 6$ array antennas are placed orthogonally to each other, so the vertical polarization and horizontal polarization are achieved. Each vivaldi antenna is followed by a phase shifter in order to achieve beam scanning. The six-way power divider has a current amplitude ratio of 0.32:0.6918:1:1:0.6918:0.32 according to the principle of Taylor array. The switch circuit is applied to choose polarization mode. The simulation results show that the −10 dB bandwidth of the antenna is extended covers X-band from 9.6 to 11.1 GHz, gain of the antenna is more than 20dB, and the side-lobe is 13.7dB, 14.0dB and 13.2dB lower than the main lobe in directivity diagram of the E-plane at 10GHz when the electrical scanning is 0deg, 10deg and 20deg, respectively. It is suitable for application of X-band phased-array antenna.