Enhancement of directivity of source radiation using parabolic cylinder made of left-handed metamaterials

We explore radiation of a line source within a parabolic cylinder made of left-handed metamaterials. The far field radiation patterns show the metamaterial parabolic cylinder can enhance the directivity of the line source radiation. It is found that the focal length and the feature length of the parabola affect the directivity. Further improvement of the directivity is realized by changing the shape of parabolic end by a metallic circular arc, which also reduces the total size of the parabolic cylinder. Finally, we compared the backscattering cross section (BCS) between the traditional parabolic reflector and the proposed parabolic cylinder with the same size and found the parabolic cylinder had much less BCS.