Multilayer Minkowski Reflectarray Antenna with Improved Phase Performance

We propose a multi-layer unit cell consisting of Minkowski fractal shaped reflector with aperture coupled phasing stubs to obtain a broad phase range for the reflectarray antenna with smaller unit cell size and inter-element spacing compared to some other studies in the literature. In the study, simulations are conducted using HFSS(TM) program with Floquet Port incidence. A unit cell with two cycles of phase range and very low reflection loss is designed. 21.9% shrinkage is achieved in patch surface area using Minkowski fractals. Subsequently, proposed unit cell is used to design and fabricate a full scale 221 element reflectarray antenna. At 10 GHz, simulation results are compared with measured data and good agreement is observed.