DNG metamaterial loaded dual wideband MIMO antenna with mitigated mutual coupling for 5G n257/n258/n260/n261 NR networks

A compact, efficient, dual wideband MIMO antenna with DNG metamaterial is designed for millimeter-wave 5G applications. The metamaterial has DNG (double negative) permittivity and permeability within dual resonance bands. The MIMO antenna without metamaterial configuration features two adjacent symmetric radiating elements with maximum corresponding isolation of $-$ 29.05 and $-$ 26.09 dB within the corresponding bands. To alleviate mutual coupling further, a metamaterial is optimally positioned amid the two elements on the substrate’s top surface, enhancing isolation to $-$ 39.81 and $-$ 42.81 dB. The antenna has a wide bandwidth of 10.43 GHz (20.22 - 30.65 GHz) for the first band and 7.23 GHz (35.27 - 42.5 GHz) for the second operating band. This compact antenna (26 mm $\times$ 14.5 mm) provides 5.5 and 5.2 dBi peak gains within respective bands. Additionally, the envelope correlation coefficient remains below 0.045 for the first band and 0.04 for the second, indicating robust diversity characteristics. As a result, the prescribed MTM-MIMO antenna proves to be a viable option for mm-wave applications, ensuring its compatibility with various 5G new radio (NR) frequency bands n257, n258, n260, and n261. This versatility facilitates its deployment in multiple countries, including Japan, Sweden, the EU, the US, South Korea, Canada, and Australia.