| 摘要 |
A lens assembly 30 comprises at least one cylindrical electromagnetic lens 320 and at least one hemi-cylindrical electromagnetic lens 310 and 330. The lenses have substantially parallel revolution axis and vary in dielectric permittivity, for example radially in concentric rings according to Luneburg law. A planar face of the semi-cylindrical lens 315 is reflective. Metal shielding 31, 33 may be provided as a wave guide to guide the electromagnetic signal substantially parallel to the permittivity gradient of the lenses. An antenna system 40 may comprise the lens assembly 30 mounted on the corner of a substrate (410, figure 4), wherein each layer of the lens assembly 30 converts a spherical wave from a point source (412, figure 5) to a plane wave (500, figure 5) by refraction, with the planar face 315 of the hemi-cylindrical lens reflecting the beam. The lens assembly may achieve a steering range of 180 to 270 degrees. |
