A dual‐band linear‐to‐circular polarization converter with robustness under oblique incidences

A dual‐band linear‐to‐circular polarization converter is proposed and experimentally demonstrated in this work. The structure consists of four identical meander‐line layers separated by air. The converter transforms y ‐polarized waves into left hand circular‐polarized waves in 19.7 to 20.2 GHz, and x ‐polarized waves into right hand circular‐polarized waves in 29.5 to 30 GHz, corresponding to the dual‐band characteristic. With the incident angle ranging from 0° to 30°, the conversion remains realizable in the two working bands, fully verifying the polarizer's robustness within 30° oblique incidence. Besides, the proposed structure is fabricated using a normal PCB process. The experimental results match well with the simulation ones, which demonstrates the feasibility of our scenario. This work is beneficial for satellite communication in the K/Ka bands.