Design of CP Reflectarray For 80 – 100 GHz Band Based on Pancharatnam-Berry Phase Theory

In this paper, the design of high gain, single layer, and low-cost circular polarization reflectarry (CPRA) for 80–100 GHz band is presented. The proposed CPRA composed by a $34\times 34$ Pancharatnam-Berry (PB) unit cells periodically distributes in xy-plane. The unit cell periodicity is 1.5 mm and dimensions of the proposed CPRA are $51.5 \times 51.5\times 0.508\ \text{mm}^{3}$ and fed by a CP horn antenna with focal-to-diameter (F/D) ratio is equal to 0.89. The required phase compensation at each unit cell across the CPRA is achieved by rotating the metallic resonator of the unit cell. The proposed CPRA is studied and the high gain beams are investigated by means of full-wave simulations. It has been shown that, the proposed CPRA realizes a 2-dB gain bandwidth of 22.22%, axial ratio (AR) < 3 dB from 80–100 GHz with maximum gain of 31.26 dB and an aperture efficiency of 45.56%. Currently, a prototype of the proposed CPRA is being fabricated and will be measured in an anechoic chamber and the measured results will be presented during the conference session.