A Reconfigurable Frequency Selective Rasorber With Switchable Transmission/Reflection/Absorption Band

Switchable frequency selective rasorbers (FSRs) have been extensively studied recently due to their out-of-band stealth and in-band electromagnetic wave manipulation abilities. Nevertheless, the vast majority of the reported FSRs are incapable of in-band waves control, including simultaneous transmission, reflection, and absorption. Herein, this article proposes a multifunctional switchable FSR that is capable of switching among all three transmission modes at the operation band. This FSR consists of two periodic layers embedded with p-i-n diodes that are separately controlled by bias voltages. By changing the states of the p-i-n diodes in each layer, the incident wave within the operation band can be manipulated continuously (transmission mode in the on-on state, reflection mode in the on-off state, absorption mode in the off-off state). Furthermore, the broad region below the operation band retains high absorptivity throughout all states. The physical properties of the multifunctional switchable FSR are investigated with an equivalent circuit model. The measured results show that a switchable operation frequency is located at 10.15 GHz, and an effective absorption band ranges from 3.8 GHz to 8.6 GHz. The proposed design has promising potential for multiple applications, such as communication for the transmission mode, protection of high-power microwaves for the reflection mode, and stealth and electromagnetic compatibility for the absorption mode.