volume | PIER Journals

Abstract

This paper presents a novel notch-based ultra-wideband (UWB) MIMO antenna with a metamaterial wall (MLB-MW) designed to significantly enhance the isolation and operational bandwidth between antenna elements. The antenna adopts a 2 × 1 notch UWB structure, integrating a metamaterial wall made of metallic lines, with an overall size of 20 × 40 × 1.6 mm³, and utilizes an FR-4 dielectric substrate (ε_r = 4.4, tanδ = 0.02). By leveraging the μ-negative characteristics of the MLB-MW, the antenna achieves a 10 dB improvement in isolation across the C, X, and Ku frequency bands. Its impedance bandwidth (|S₁₁| < -10 dB) extends from 6.09-13.07 GHz to 5.51-15 GHz, with a relative expansion rate of 36%. Additionally, key performance parameters of the MIMO antenna are comprehensively evaluated: the envelope correlation coefficient (ECC) remains below 0.01 across the entire frequency band; the diversity gain (DG) is close to 10 dB; and the total active reflection coefficient (TARC) stays below -10 dB across the entire operating band, indicating excellent channel independence and diversity performance. Experimental results verify the feasibility and effectiveness of this antenna in 5G base station applications.

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Dr. Shuming Liu

Professor Jingchang Nan

Dr. Yifei Wang