Abstract
As one of important applications of metamaterials, the metamaterials-based antennas were introduced in this chapter. Firstly, theoretical background regarding the antenna was given. Then two types plasmonic structures being used as antennas: electromagnetic band-gap (EBG) structures-based antenna and waveguide slit array antenna were presented. Some experimental results were demonstrated also. Some unique properties of the antennas were shown in terms of these results.