volume | PIER Journals

Abstract

In this study, a novel symmetrical complementary double-split-ring resonator structure is proposed, operating in the frequency bands of 2.39-2.44 GHz (covering the core 2.4 GHz WLAN band) and 3.45-3.60 GHz (covering a key sub-band of n78 for 5G communications), to reduce the coupling of multiple-input multiple-output (MIMO) antennas within these two frequency bands. To align with the trend of antenna miniaturization, the inter-element spacing is only 0.08λ₀. The measured results show that after loading the metamaterial, the antenna coupling in the operating bands is reduced by 0-10 dB and 8-23 dB, respectively, and the coupling in the two bands is below -17 dB and -27 dB, respectively. The peak gains achieved are 3.12 dBi and 4.51 dBi in the two bands. The ECC is less than 0.02, indicating excellent gain performance and effective decoupling capability of the MIMO antenna.

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Dr. Xuemei Zheng

Mr. Jiafu Xing

Dr. Tongchao Zhang