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A polarization independent conformal wideband metamaterial absorber has been proposed in this study. The proposed absorber unit cell consists of a circle and a slotted sector, loaded with four lumped resistors between them to improve the absorption bandwidth. Measured and simulated results exhibit more than 90% absorption in the frequency band from 3.90 GHz to 10.5 GHz under the normal incidence angle, and the fractional bandwidth is 91.6%. The proposed absorber is polarization independent due to the symmetrical nature. The absorber unit cell is compact in configuration with a unit cell size of 0.16 λo × 0.16 λo, where λo is the wavelength at 3.9 GHz and the substrate thickness is 0.098 λo. Once the proposed absorber is wrapped on the cylindrical surface, it shows good absorptivity in the absorption frequency band. The effects of many designed parameters have been studied to understand the performance of the wideband absorber. To recognize the absorption phenomenon of the absorber, normalized impedance, electric field distribution, and surface current density have been demonstrated. Finally, the proposed conformal absorber fabricated and measured the absorption for flat and curved surfaces, which exhibits good agreement between the simulated and the experimental results.

This paper presents a compact dual band metamaterial antenna for WiMAX applications. The reported antenna was based on using a metamaterial modified left handed transmission line unit cell. The designed antenna was introduced to operate with the WiMAX lower 2.4 GHz band and upper 5.8 GHz band.The designed antenna has the advantages of its compact size (only 2 X 3) cm 2 . Compared to the conventional patch length, the designed patch radiator is only 25% at 2.4 GHz and 60% 5.8 GHz. The antenna designed was discussed theoretically and its performance was verified using the electromagnetic full wave simulations. The results confirm that the antenna can introduce the dual bands operation with return loss better than 15 dB at each operating band. Moreover, the radiation pattern is almost omnidirectional at the two bands. Keywords-Metamaterial, multi-band antenna, dual band, left handed, WiMAX.I.