Circularly polarized rectifying reflectarray antenna at C-band

In this paper, circularly polarized rectifying reflectarray antenna has been proposed. Cylindrical dielectric resonator (CDRA) antenna is used to exhibit left-hand and right-hand circular polarizations. As well, the antenna operates in a linear polarization mode on the basis of the bias states of two PIN diodes. The antenna is used to feed the reflectarray to increase its gain in a certain direction. A single piece of dielectric material sheet is divided into 17×17 unit-cell elements to build up the reflectarray. Each unit cell has four circular holes of equal diameters and is supported on the perfect conducting ground plane. The total phase variation of 360° is achieved as the hole radius is varied. Full-wave analysis using the finite integration technique is used to calculate the radiation characteristics of the reflectarray with its feed. The reflectarray is designed at 5.8 GHz at C-band to concentrate the incident waves on the receiving antenna. It is lite weight, small size and low cost. Rectifying circuit components composed of a matching network, two-stage voltage doubling circuit, DC-pass filter and a resistive load are designed. Based on the analysis of ADS software, this rectification circuit has the maximum conversion efficiency of 71% at 5.8 GHz on the load of 1200-Ω.