Two dimensional luneburg lens implemented with a loaded wire grid

A new realization of the two-dimensional Luneburg lens using the capacitive loading of a wire grid is presented. The values of the load capacitances control the refractive index of the lens. The transformation of the circular phase front of the line source located on the edge of the cylindrical lens to planar phase front on the opposite side of the lens is demonstrated. The effect of the distance between the wires in the grid on the performance of the discretized Luneburg lens is investigated. It is shown that when the distance between the wires increases the source should be shifted inside the discretized lens to obtain the optimum performance. However, the achieved optimum directivity remains constant regardless of the distance between the wires.