Dual mode metamaterial antenna for wideband applications

A dual mode metamaterial antenna is proposed. The antenna is a monopole loaded with metamaterial (MTM) unit cell. An asymmetrical coplanar waveguide (ACPW) technique is employed to achieve a certain degree of compactness. The overall size of the antenna is 0.320 x 0.210 (39 x 25 mm2) at 2.5 GHz. The bandwidth enhancement is achieved when zeroth-order resonance (ZOR) mode is merged to the positive order resonance (POR) mode. Simulated results show that a bandwidth enhancement of 39% is obtained with the radiation efficiencies of 75% and 91% for the ZOR and POR modes, respectively. The return loss response shows that the designed antenna is matched and able to work well within a frequency range of 2.4567-3.6008 GHz, which is suitable for WiMAX applications (2.5-2.69 GHz/3.3-3.365 GHz). The simulated and measured antenna performances in terms of return loss and the radiation patterns are presented and compared. (c) 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1846-1850, 2014