Metallic Elements Inside a Mismatched Luneburg Lens: Experimental Validation at V-band

We implement a cylindrical mismatched Luneburg lens on PCB at V-band, including metallic elements inside the GRIN lens. The lens has a relative dielectric permittivity of 2.2 at its edge, while the exterior medium is air. The judicious choice of dielectric substrate, and the introduction of metallic posts at carefully selected positions, both enhance the bandwidth and radiation properties of the GRIN lens antenna. Measurements confirm that this design can produce a stable fan-shaped beam over a 10 GHz bandwidth and at multiple excitation points covering a 90 degree angular range.