Offset fed diamond shaped split ring (DSSR) planar metamaterial antenna

In this paper the authors have presented a planar metamaterial antenna using offset fed diamond shaped split rings (DSSR). The structure behaves as normal patch antenna when the split rings are excited at normal cuts on Y-axis whereas the same structure exhibits metamaterial characteristics when fed at offset cut at an angle ??=45??. In offset cut the excess inductance and capacitance due to microstrip discontinuities get eliminated and the antenna structure exhibits metamaterial characteristics. The normal patch antenna resonates at 8.11 GHz having bandwidth of 444 MHz. The resonant frequency of metamaterial planar antenna is 8.27 GHz with the bandwidth of 490 MHz. Thus in metamaterial antenna configuration the bandwidth is enhanced by 46 MHz. The equivalent circuit of the offset fed DSSR is presented to justify the theoretical and simulated resonant frequencies. Both normal cut and offset cut antenna structures are simulated using IE3D electromagnetic simulator of Zeland software, incorporation.