Summary Design, simulation and measurement of a broadband epsilon‐near‐zero (ENZ) metasurface‐based gradient refractive index (GRIN) Luneberg lens has been presented with different antennas demonstrating gain enhancement and producing highly directive beams. The unit‐cell meta‐structure consists of a conducting ring with monopoles at 45°. The horizontal radius of the conducting ring is varied to vary the refractive index of the structure. Unit cells with varying refractive index are arranged in a 2D plane to produce a planar Luneberg lens structure. The lens is demonstrated to produce a gain improvement of 6–13.2 dBi for different configurations and different antennas including a microstrip patch antenna and horn antenna both in simulation and measurement while maintaining the total efficiency of the antenna being used with the lens.

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