Circularly polarized microstrip reflectarray with microstrip antenna feed

A circularly polarized microstrip reflectarray antenna with a microstrip antenna feed and patches having variable rotation angles is proposed. A parametric study for three different configurations, namely a single patch, 1 × 3 and 3 × 1 array is presented. The plus-shaped and 3 × 3 array configurations have also been studied. It is observed that an optimum axial ratio bandwidth of around 45 MHz is obtained for 1 × 3 and 3 × 1 arrays when the patches are rotated by +40°. A gain of around 7.5 dBi is obtained in 1 × 3 and 3 × 1 arrays. For plus-shaped and 3 × 3 configurations an optimal axial ratio bandwidth of 40 MHz and a gain of around 10 dBi are obtained.