A Luneburg Lens antenna Composed of Gradient Index Metamaterials based on 3D printing

A Ku-band Luneburg lens antenna composed of gradient index metamaterials is presented made by 3D printing. The focusing condition of the lens, requiring a gradient refractive index, is achieved by using the Photonic crystal structure. A dielectric column diamond structure is chosen as the Photonic crystal unit cell since its permeability and permittivity can keep constants when the unit cell size is much smaller than the working wavelength. A standard retrieval procedure is used to determine the relationship between the dielectric column radius of the unit cells and the refraction index. Therefore, a new kind of Luneburg lens composed of the diamond structure dielectric column arrays is constructed. Simulation results have shown that the proposed Luneburg lens, which operating in Ku-band, has an excellent focusing ability.