A Curved Structure for Ultra-Wideband Metamaterial Absorber in UHF Band

An ultra-wideband absorber for UHF band is presented, which is composed of symmetrically incurved metal lines loaded with eight lumped resistors. The structure achieves 106.5% absorption bandwidth between 0.83GHz and 2.72GHz. The absorptance of 99.97% and 99.99% were respectively achieved at 1.0GHz and 2.35GHz. For TE and TM polarizations, when the incident angle is less than 40°, the absorptivity of the absorber is maintained over 80% within 1GHz to 2.75GHz. The structure can be miniaturized at low frequencies with a size of 0.04λ L ×0.04λ L . (λ L is the wavelength at 0.83GHz).