A design of Luneberg lens using symmetry metamaterial unit cell

A two-dimensional Luneberg lens designed using a symmetrical metamaterial cell to operate a wide frequency band covering 8GHz-12GHz is proposed and studied. The proposed Luneberg lens is composed of an array of complementary circle cells and embedded in a parallel-plate TEM waveguide. Due to high resonant frequency of the complementary circle cell, the equivalent refractive index is nearly constant across the designed frequency band. With the symmetry of the circle cell, the proposed lens can transform cylinderical wave excited by the source at arbitrary location on the surface of the lens to plane wave. Numerical results show good performance of the proposed lens.