Design of printed antennas on reactive impedance substrates for circular polarization operation in S-band

Circularly-polarized antennas printed on optimized reactive impedance substrates (RIS) are studied in S-band for telemetry applications. The individual roles of the RIS geometry (45°-rotated rectangular elements) and of the radiating element configuration (patch antenna loaded or not by a slot) are investigated numerically and experimentally. In particular, we demonstrate that a single-feed CP antenna printed on the optimized RIS can exhibit a large CP bandwidth (more than 10%) with a low profile.