Design, implementation and test of a broadband isoflux beam reflectarray antenna for GEO satellites

Abstract

The feasibility of deploying reflectarray antennas on synchronous satellites with the aim of achieving isoflux beam for optimum earth coverage is investigated. Due to the difference in free space loss from the satellite to different points on the earth, a conventional collimated beam pointing to the Earth centre is not efficient. So, there is a need for a radiation pattern whose gain increases at the line of sight angles to the horizon and diminishes towards the centre. Accordingly, a single-layer reflectarray antenna composed of loaded square patches is fabricated and tested. In this regard, the dimensions of reflectarray elements are adjusted using a robust optimization technique that minimizes the adverse effects of frequency dispersion in the intended frequency bandwidth. Experimental results demonstrate a stable radiation pattern with a relative bandwidth of about 11% at 14.25 GHz centre frequency.

Keywords:

• Reflectarrays
• shaped beam antennas
• isoflux beam
• satellite communication

Additional information

Funding

This work was supported by K.N. Toosi University of Technology