Design and Optimization of Broadband Single-Layer Reflectarray

A novel broadband single-layer reflectarray for satellite communications has been presented. The design and simulation results are obtained and discussed. The element in the reflectarray provides a nearly 360 degrees linear phase range. The reflectarray is fed by a printed microstrip log-periodic dipole antenna. The broadband characteristic of the reflectarray is obtained due to the sub-wavelength of the element space. In order to increase the gain bandwidth of this reflectarray further, an optimization technique was utilized to minimize the frequency dispersion. Finally, a prime-focus 256- element reflectarray at C band is designed and simulated. The obtained 3-dB gain bandwidth reaches 30.8% (from 4.4 to 6.0GHz).