Frequency selective subreflectarray for S/X band reflector antenna

A frequency selective subreflectarray (FS-SR) is proposed for dual band Cassegrain reflector antenna. The proposed subreflectarray is composed of three layers, namely, one phase shifting layer (PSL) and two frequency selective layers (FSLs). The two FSLs could block the X band wave and pass the S band wave. The PSL is used to vary the reflection phase of circularly polarized X band wave up to 720° through element rotation. A FS-SR is modeled and simulated, and its scattering patterns under feed illuminations are obtained. The simulation results show that the FS-SR could indeed support S/X dual band operation. A prototype is fabricated and measured for verification.