All-metal wideband folded transmitarray antenna design

By introducing the polarization conversion layer concept, this paper designs an all-metal folded transmitarray antenna with a compact structure that works in the X-band. The antenna is mainly divided into the feed antenna, the polarization conversion surface of the upper layer, and the transmission array of the lower layer. The polarization conversion surface can deflect the linear polarization wave by 90°, and when the deflected beam is transmitted through the array, the lower transmission array is phase compensated to the beam, which can achieve a high-gain beam. The profile height of this antenna can be reduced to one-third of the conventional transmitarray antenna due to optical path folding. The simulation results verify the good performance of the antenna, with the highest gain of 24 dBi at the center frequency point of 9 GHz, the aperture efficiency is 30.4%, the 1dB gain bandwidth covers 8 – 9.5 GHz, and the relative bandwidth can reach 17.1%.