Phase distribution analysis of reflectarray resonant elements based on linear and non-linear materials

Properties of substrate material play an important role in the design of reflectarray antenna. In this work linear and non-linear dielectric properties of substrate materials are discussed thoroughly. Rogers RT/d 5880 and K-15 nematic are used as linear and non-linear dielectric materials respectively, to design different reflectarray resonant elements in X-band frequency range. Simulated and measured results of different reflectarray resonant elements printed on Rogers substrate are discussed thoroughly. Simulations based on CST computer model are performed to analyze dynamic response of three different reflectarray resonant elements printed on K-15 nematic material. It has been demonstrated that the ring element based on linear material offers higher static phase range of 310° as compared to dipole and rectangular elements which offer 285° and 200° respectively. Furthermore the rectangular element based on nonlinear material is observed to offer a narrower dynamic phase range of 90° as compared to dipole and ring elements which offer 190° and 200° respectively.