Polarization-independent wideband meta-material rasorber with wide transmission window based on resistor loaded circular and split ring resonators

• Published in: Advanced electromagnetics Vol. 14; no. 1; pp. 14 - 22
• Main Authors: Kumar, A., Sen, G., Ghosh, J.
• Format: Journal Article
• Language: English
• Published: Advanced Electromagnetics 20.02.2025
• Subjects: Band-pass filter; Frequency selective surface; Microwave absorber; Radar cross-section; Radomes
• ISSN: 2119-0275; 2119-0275
• DOI: 10.7716/aem.v14i1.2538

A dual polarized with high absorption to right side and wide in-band transmission is proposed in this study. Our proposed design consists of four modified split ring resonators on the top layer and four lumped resistor of 150 Ω value is connected between them to absorb the incoming EM wave in the out-ofband frequency regime.The circular slotted cut on the lower layer is responsible for in-band transmission. The lower layer is behaving as a ground plane for out-of-band absorption and and passing a range of frequency for the transmission band. So, bottom layer is behave as a band-pass frequency selective surface filter. The design has an overall thickness of 0.18λ and a fractional bandwidth of approximately 113%. The entire design exhibits an insertion loss of 1.10 dB at the transmission band at around 5.93 GHz and exceeding 80% absorption from 2.8 GHz to 10.0 GHz. The proposed design is polarization insensitive due to its symmetrical design and angularly stable up to 45Åã for both both TE and TM polarization of wave. The novelty of the proposed design lies in its wide out-of-band absorption, wide in-band transmission, minimal thickness, high fractional bandwidth, good angular stability, cost-effectiveness, accessibility through the use of inexpensive materials for manufacture and simple design. To analyze the proposed rasorber, we have investigated the polarization behavior, surface current distribution and design other parameters. Lastly, the proposed structure has been constructed using PCB technology and validated in a semi-anechoic chamber. The simulated and measured responses exhibit a high degree of agreement.