| 摘要 |
<p>An antenna system comprises a cylindrical electromagnetic lens 1 with a variation in dielectric permittivity for guiding a signal to form an output signal beam and a dielectric member 2 arranged to receive and focus the output beam. The focused output beam from the dielectric member 2 is in a plane perpendicular to the planar face of the lens 1. The dielectric member 2 has a variable height in a direction parallel to the axis of the cylindrical lens 1. The dielectric member 2 may be a ring shape surrounding at least half the circle, in the azimuth plane, of the cylindrical electromagnetic lens 1 and faces a lateral face of the said lens. The dielectric member 2 may have symmetrical or non-symmetrical portions. The height variation of the dielectric member 2 may be continuous and/or discontinuous, such as a step change, along it edge portions. Parts of the dielectric member 2 may be formed from different materials with different permittivity values. The dielectric member 2 may be detachably mounted in the antenna system and it may be adjustable around the axis of the lens 1. The lens 1 may include a conductive top shield 3 and a bottom shield. The antenna system may be used in streaming data between a personal computer and video projector units at different distances from each other.</p> |
