Static and Dynamic Beamforming with Huygens' Metasurface Antennas

Most antenna applications require certain control of the radiation characteristics, such as the direction of the beam, the directivity and the sidelobe level. It may also be desirable to steer the beam dynamically. Although control of the far-field region of antennas has been traditionally achieved by antenna arrays, the feeding networks of such arrays result in bulky designs and increase power losses. A promising alternative is the use of metasurfaces that transform the fields of a simple source to aperture fields corresponding to prescribed radiation patterns. In this paper, different ways are presented to obtain both static and dynamic beamforming with Huygens' metasurfaces.