A novel design of wideband, ultra-thin, wide-angle metamaterial microwave absorber has been presented. The unit cell of the proposed structure is designed by using parametric optimization in such a way that absorption frequencies come closer and give wideband response. For normal incidence, the simulated FWHM bandwidth of the proposed structure is 1.94 GHz, i.e. from 5.05 GHz to 6.99 GHz and -10 dB absorption bandwidth is 1.3 GHz from 5.27 GHz to 6.57 GHz. The proposed structure has been analyzed for different angles of polarization, and it gives high absorption (more than 50%) for oblique angles of incidence up to 60˚. The designed absorber is in low profile with a unit cell size of λ0/6 and ultrathin with a thickness of λ0/32 at the center frequency of 5.92 GHz corresponding to 10 dB absorption bandwidth. The current and electromagnetic field distributions have been analyzed to understand the absorption mechanism of the absorber. An array of the proposed absorber has been fabricated and experimentally tested for various polarization angles and oblique incidences of electromagnetic wave. The proposed absorber is well suited for surveillance and other defense applications.
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