Analysis of Wideband Reflectarrays based on Different Progressive Phase Centers

A reflectarray unit cell element with a tilted side is proposed in this work for wideband operation at 26 GHz frequency. The scattering parameter measurement of the proposed element has been performed and a reflection phase swing of more than 600° is achieved. The overall size of the element has been varied to acquire the progressive phase distribution with two different phase centers of 180° and 360°. Each progressive phase distribution is used to design a 20 × 20 reflectarray antenna. It has been shown that, the reflectarray with 360° phase center acquired a wider -3dB gain drop bandwidth of 3.3 GHz as compared to 2.08 GHz of 180° phase centered reflectarray. Alternatively, the 180° phase centered reflectarray attains a lower side lobe level of -12.7 dB with 22.9 dB gain as compared to a side lobe level of -8 dB with 25.4 dB gain of 360° phase centered reflectarray.