An energy-selective rasorber with switchable transmission/absorption band

In this paper, an energy selective rasorber with integrated frequency selective rasorber and energy selective surface (ESS) functions is proposed, which realizes the dynamic switching between wave-transparent function at low-power level and wave-absorbing function at high-power level by embedding PIN diodes. The design of the structure consists of an upper broadband absorbing structure and a lower adjustable frequency-selective structure. At low power, the structure exhibits effective wave-absorbing function with Insertion Loss (IL) less than 0.5 dB and reflection coefficient less than −10 dB in the 5.6–6.4 GHz band, while at high power, both the reflection and transmittance coefficients are less than −10 dB. Compared with the existing ESS designs, the proposed structure is able to realize the effective switching between the transmitting and absorbing bands, thus providing both protection and stealth functions. In addition, the design exhibits high absorption efficiency, low IL, and polarization insensitivity, demonstrating its potential for a wide range of applications in electromagnetic protection.