Directivity enhancement of line source radiation by hollow cylinder made of left-handed material

We have investigated radiation of a line source within a hollow cylinder made of lossless left-handed materials (LHMs). We calculate field radiation patterns of the line source and find that the LHMs cylinder functions directivity enhancement of source radiation. The study shows that the position of the source and the thickness of the LHMs greatly affect the directivity, and there is an optimized source position and thickness of LHMs for the best directivity.