A Wideband Circularly Polarized Reconfigurable Element for Beam-Scanning Transmitarray Antenna Applications

This paper presents a wideband one-bit reconfigurable circularly polarized transmission element designed for beam-scanning transmitarray antennas (TAs). The transmission element is designed based on the fundamental structure of a magnetoelectric dipole which exhibits a wide bandwidth due to the resonance combination of the electric dipole and magnetic dipole. A receiving magnetoelectric dipole and a transmitting magnetoelectric dipole are integrated to form the proposed receiving-transmitting (R-T) transmission element. The receiving magnetoelectric dipole is a center-fed, linearly polarized magnetoelectric dipole that is soldered with two p-i-n diodes. By electronically controlling the state of the p-i-n diodes, a reconfigurable one-bit transmission phase can be generated. The transmitting magnetoelectric dipole is a circularly polarized magnetoelectric dipole fed by an L-shaped feed probe. To verify the performance of the transmission element, we conducted simulations using HFSS. The simulation results indicate that the transmission bandwidth ranges from 13.0 GHz to 17.8 GHz, achieving a bandwidth of 31.2 % with a transmission amplitude better than -2.0 dB. The proposed transmission element is an ideal candidate for beam-scanning TA design applications.