High-performance low-profile green electromagnetic interference shielding material for 5G mm-wave using characteristic mode theory

Abstract

With the rapid development of 5G communication technology, high-frequency electromagnetic interference (EMI) shielding plays a vital role in the normal operation of electrical and electronic equipment and systems, and has attracted surging interest in 5G mm-wave applications. However, many current EMI shielding materials contain highly conductive materials, resulting in strong secondary reflection and environmental pollution. Here, we propose a green high-performance EMI shielding material for 5G mm-wave based on a metamaterial absorber (MMA). Characteristic mode theory and equivalent circuit are employed to inversely design the unit cell’s dimension and structure, as well as the resistive value of the proposed MMA. We reveal that from 22 to 43.5 GHz, the shielding effectiveness of higher than 30 dB, and the standard green index of SER < 3.01 dB and g s ⩾ 1 can be realized whether the MMA is flat or even bent. Excellent agreement between the measured and simulated results verified the high performance of the proposed EMI shielding MMA. The transmittance of over 85.84% can be achieved within the 380 ∼ 800 nm spectrum. The proposed green EMI shielding material integrates multi-functionalities of low profile, flexibility, polarization-insensitiveness, wide-angle, and optical transparency, and can find potential applications in EMI shielding in complex electromagnetic environments.