Low profile perforated folded transmitarray for polarization diversity

In this paper, low profile perforated folded transmitarray for polarization diversity is proposed for modern communications systems. A high-gain 17 × 17 unit-cell elements folded transmitarray antenna is designed using perforated dielectric substrate at 2.45 GHz. The waveguide simulator is used to calculate the required compensation phase shift for the transmitarray design through the variation of the perforations radii. A novel cylindrical DRA antenna with circular Y-shaped feed line is introduced as a feeder for the folded transmitarray. The polarization diversity is controlled by switching two PIN diodes ON/OFF according to the required polarization. Left-hand, right-hand, and linear polarizations are obtained. A full-wave simulation for the perforated folded transmitarray fed by the DRA is carried out. The radiation characteristics of the perforated transmitarray are investigated. The proposed antenna introduces 1-dB gain bandwidth of 335 MHz and axial ratio of 0.73 dB.