Highly Transparent Tunable Microwave Perfect Absorption for Broadband Microwave Shielding

Li, Dongdong; Hu, Xiaojun; Gao, Bingtao; Wang, Yin; Chen, Hongsheng; Qian, Haoliang

doi:10.2528/pier22101901

Cited by 10 publications

(2 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…To comprehend the mechanism by which a magnetic material can reduce EMI, it is essential to consider its permeability (µ) [40,41]. The complex relative permeability of a material can be partitioned into real and imaginary components, which are dependent on the frequency, as shown in Figure 3.…”

Section: Magnetic Materials Characterizationmentioning

confidence: 99%

Advanced Characterization of a Hybrid Shielding Solution for Reducing Electromagnetic Interferences at Board Level

Victoria,

Suarez,

Martinez

et al. 2024

Electronics

View full text Add to dashboard Cite

The development of new advanced functionalities, miniaturization, and the aim of obtaining optimized performance in electronic devices significantly impacts their electromagnetic compatibility (EMC). As electronic components become more densely packed on a printed circuit board (PCB), unintended coupling between components can cause electromagnetic interference (EMI). These requirements result in design restrictions that make using a board level shield (BLS) essential in reducing intra-system EMI in PCB designs. This contribution focuses on studying and characterizing a BLS solution based on combining a noise suppression sheet (NSS) with an aluminum layer to reduce intra-system EMI coupling. This hybrid solution has the advantage of providing a shielding option that does not require any electronic redesign. It does not need a footprint or a ground connection as it can be affixed over the EMI source. The solution is expected to provide higher attenuation levels than using only an NSS by combining the absorbing properties of the magnetic material and the loss mechanism of the metal. In order to verify the effectiveness of the hybrid BLS proposed solution, the magnetic near-field emissions of an EMI source are analyzed in this study. The experimental measurements and simulated results demonstrate a significant increase (51.6 dB at 1 GHz) in the shielding effectiveness (SE) provided by the proposed solution compared to a conventional NSS.

show abstract

Section: Magnetic Materials Characterizationmentioning

confidence: 99%

Advanced Characterization of a Hybrid Shielding Solution for Reducing Electromagnetic Interferences at Board Level

Victoria,

Suarez,

Martinez

et al. 2024

Electronics

View full text Add to dashboard Cite

show abstract

“…明电阻膜FSS吸波结构一直是微波吸波体领域的研究热点 [47,48] , 然而对电阻膜加工带来的方阻不稳定影响FSS吸波结构性能问题 [35,49,50] 的研究还停留在对方阻扫参讨论 [31,33]…”

Section: 尽管电阻膜Fss吸波结构尤其是近几年透unclassified

Ultra-wideband thin frequency-selective surface absorber against sheet resistance fluctuation

Wang,

Sun,

Zhang

et al. 2024

Acta Phys. Sin.

View full text Add to dashboard Cite

The design of thin frequency selective surface (FSS) absorbers based on resistive films that meet the requirements of broadband, polarization independence, incident angle stability, and strong absorption is a challenging task. Fabrication tolerance of resistive film can result in fluctuations in sheet resistance, which negatively impact the absorber performance. To tackle these problems, this paper firstly investigates how sheet resistance fluctuations affect the absorbing performance of resistive film FSS absorbers. Through analysis of simulated current density distribution and impedance, it is revealed that the diversity of current paths provides an effective way to mitigate the influence of sheet resistance fluctuation. This is achieved by enabling flexible variation of surface current in response to sheet resistance fluctuates. Consequently, the variation of input impedance of the FSS absorber due to the fluctuation of sheet resistance is suppressed within a small range. Then, a method for bandwidth extension is proposed by employing the complementary variation of FSS impedance with frequency at different layers. By combining this approach with a miniaturization design, a thin and light FSS absorber is developed that exhibits ultra-wide bandwidth, polarization independence and angle stability while mitigating the effects of sheet resistance perturbation. The proposed FSS absorber achieves a 90% absorption bandwidth from 1.50 GHz to 20.50 GHz, covering Ku, X, C, S bands as well as part of the L and K bands, with a relative bandwidth of up to 173%. The absorber has a thickness of 0.093 λ<sub>L</sub> for both transverse electric (TE) and transverse magnetic (TM) polarizations, yielding a figure of merit (FoM, the ratio of the theoretical minimum thickness to the actual thickness) of 0.95, indicating that the thickness is close to the theoretical limit. The absorber retains over 90% absorption rate for TM polarization at an incidence up to 70° and 80% absorption for TE polarization at an angle of 45°. Furthermore, the 90% absorbance bandwidth of the absorber remains at 167.0% when the sheet resistance of any FSS layer fluctuates within a range from 12 Ω/sq to 30 Ω/sq. A prototype of the proposed FSS absorber is fabricated and measured, yielding experimental results that are in good agreement with the simulation results, thus validating the effectiveness of the proposed method.

show abstract

Multiplexing Meta‐Illusion with High Correlation in Both Near‐ and Far‐Field Region

Huang,

Guan,

Zheng

et al. 2024

Laser & Photonics Reviews

View full text Add to dashboard Cite

Microwave illusion, which can generate the scattering field of objects that don't exist to deceive the detecting devices, is an important and advanced technology in modern science. The conventional illusion device is limited by the narrow working band, non‐flat structure, or single functionality, which is inconvenient for electromagnetic integration. The newly multiplexing metasurfaces provide an effective method to achieve microwave illusion due to their excellent ability in wavefront tailoring. Here, a dual‐band microwave illusion enabled by multiplexing metasurface is proposed, and such a device can simulate two independent scattering fields of real objects at two separate frequencies by recording the near‐ and far‐field information. As a proof of concept, a meta‐illusion, realizing the electromagnetic information of the scaled‐down Sydney Opera House and Pyramid, is designed and fabricated. Microwave experiments are performed to demonstrate the predicted effects. The results show high correlation properties in both near‐ and far‐field characterizations, which is 83%, 80%, and 91%, 80% at two operating frequencies, respectively, verifying the high performance of the meta‐illusion. The findings may motivate the realizations of high‐performance meta‐illusions in other frequency domains and meta‐devices with complex functionalities.

show abstract

Highly Transparent Tunable Microwave Perfect Absorption for Broadband Microwave Shielding

Cited by 10 publications

References 28 publications

Advanced Characterization of a Hybrid Shielding Solution for Reducing Electromagnetic Interferences at Board Level

Advanced Characterization of a Hybrid Shielding Solution for Reducing Electromagnetic Interferences at Board Level

Ultra-wideband thin frequency-selective surface absorber against sheet resistance fluctuation

Multiplexing Meta‐Illusion with High Correlation in Both Near‐ and Far‐Field Region

Contact Info

Product

Resources

About