A Triple Band Four Folded Metamaterial Absorber in the C- and X-band Spectrum

Developing ultra-thin four folded triple band metamaterial absorber (TMMA) in C - and X-band with near unity absorption has found to be a significant challenge. In this paper a novel compact metamaterial absorber (MMA) design has been introduced for C and X band applications. This absorber features resonance frequencies at $4.89 \mathrm{GHz}, 7.11 \mathrm{GHz}$ and 9.07 GHz with peak absorptions of $97.09 \%, 99.99 \%$ and $99.94 \%$. This MMA, characterized by its simple designed resonator, employs a slim 1.2 mm thick substrate. Furthermore, polarization insensitivity is achieved for the design, and it exhibits wide incident angle stability. To check its reliance under harsh environment, bending is also tested for both TM and TE modes that shows satisfactory absorption performance. An equivalent circuit is designed using the Advanced Design System software, to represent its electromagnetic behavior in this region. The proposed unit cell can be used for wireless communication for narrowband in microwave regions. Moreover, the frequency range of both $\mathbf{C}$-band and $\mathbf{X}$-band is covered by this unit cell, which has potential applications such as C-band satellite downlink.