Generation of Multibeam Radiation Using an Array of High Refractive Index Vertical Slabs

This letter proposes a technique employing anisotropic dielectric slabs to generate multibeam radiation pattern from a single antenna with linear or circular polarizations. The anisotropic slabs having higher and lower refractive indices along electric field polarization and propagation direction respectively are realized using anisotropic metamaterial unit cells. First, a microstrip patch antenna is loaded with the vertical metamaterial slabs in the $E$-plane to generate dual-beam radiation. Later, the technique is extended to two planes to generate quad-beam radiation. This results in a very low profile ($2.2\lambda _{0}^{3}$) quad-beam antenna system having radiation beams along $\theta =\pm 35$° with 7.5 dBi beam peaks in both planes.