Perturbation Technique to Analyze Mutual Coupling in Reflectarrays

A perturbation technique is described to investigate numerically mutual coupling in reflectarrays. We first define it and then demonstrate that the corresponding perturbation factor has the same meaning as mutual coupling within traditional phased array antennas. Finally the field perturbation approach is applied to a two-element dielectric resonator antenna (DRA) array using finite-difference time-domain (FDTD) modeling. Simulation results show that the proposed method can be used to efficiently analyze mutual coupling in real reflectarray configurations where ports do not exist and cells dimensions are not identical by nature.