Design of Broadband Microwave Absorber with 20 dB Absorption Bandwidth

A simple design configuration has been presented for broadband microwave absorber. The proposed designed structure is made using thin resistive film of indium tin oxide (ITO) to exhibits 20 dB absorption bandwidth in the frequency range of 7.36 GHz to 14.05 GHz with absorptivity nearly 99% at the normal incidence. It is first time when bandwidth is represented with respect to 20 dB of return loss instead of conventional 10 dB of return loss. This makes the design specification really stringent and needs extra attention while designing microwave absorber. Here the proposed structure is polarization insensitive and gives good oblique incidence behavior for both TE and TM. An equivalent circuit model is also derived to study the absorption mechanism of the structure.