Low-complexity frequency selective rasorber with polarization-independent switching capability

In this paper, a novel low-complexity and cost-effective switchable frequency selective rasorber (SFSR) with polarization-independent switching capability is proposed. To our best knowledge, previously reported electronically reconfigurable and polarization-independent SFSR configurations requires at least 3 distinct layers with no less than 20 SMD lumped components for each unit-cell, causing high cost and fabrication complexity. Conversely, the herein developed switchable rasorber contains only 2 layers with 6 SMD lumped elements for each unit-cell, thus significantly simplifying fabrication and reducing overall cost. To achieve the independent control over TE and TM polarizations, we separate the structure design in perpendicular directions. Two switchable bands are accomplished, whose working mode can be changed from transmission to absorption and reflection to transmission respectively, while only one is usually possessed by previous literature results. By switching the operating state of PIN diodes, the SFSR working mode type is A–T/A–A–R/T. For A–T–A–R mode, it exhibits (Formula presented) (Formula presented) dB low reflection band of 2.89–8.74 GHz, with 1.17 dB insertion loss. For A–A–A–T mode, it exhibits low reflection band of 3.67–8.2 GHz. Besides, the SFSR has angle stability of (Formula presented) (Formula presented). After the design process and numerical simulations evaluation, prototypes are fabricated through PCB technology and characterized in anechoic environment, confirming the overall approach. This work improves about 43% cost effectiveness under same capabilities and it is particularly suitable for all the applications requiring low-complexity and cost-effective fabrication, such as unmanned equipment and antennas radome.