Polarization-Tunable Microstrip Antenna Based on Double V-Type Metamaterials Cover for Microwave Energy Harvesting

With the development of communication, the electromagnetic waves in space are becoming more and more abundant, so the rectenna for microwave energy harvesting has received considerable attention. Based on the bifunctional characteristics of double V-type metamaterials cover, a novel rectenna is proposed in this letter. The simulated and experimental investigations show that by tuning the rotation angle of the metamaterials cover, the antenna achieves linear-to-circular polarization conversion at 5.8 GHz, which makes it suitable for complex microwave energy harvesting. At the same power density of linearly and circularly polarized waves, the dc power rectified by the novel rectenna is 6.5 and 4.2 dB higher than that of the original rectenna, respectively. The novel antenna with metamaterials cover presents a new option for developing multifunctional and multipolarized rectennas.