A Broadband and Wide-Angle Linear-to-Circular Polarization Converter for Mobile Microwave Wireless Power Transmission

In this letter, a broadband and wide-angle linear-to-circular polarization converter (LCPC) based on a three-layer transmissive metasurface is proposed, to solve the problem of efficiency degradation caused by polarization mismatch in mobile microwave wireless power transmission. The simulated results show that our proposed model has an axial ratio of less than 3 dB in the 4.24–6.24 GHz band (38.17% bandwidth) with a maximum insertion loss of 1.66 dB for normal incidence in both yz and xz plane. In addition, 50° incidence angle stability can also be achieved. To verify the feasibility, a sample with a total dimension of 300 × 300 × 5.105 mm³ is fabricated. The measured results demonstrate that our LCPC combines the advantages of broad band, wide angle, low loss, and low profile. With this LCPC, the received power is verified to remain stable when the polarization angle of the receiving antenna changes.