Massive metamaterial system-loaded MIMO antenna array for 5G base stations

Abstract

Abstract An integrated massive multiple-input multiple-output (mMIMO) antenna system loaded with metamaterial (MTM) is proposed in this article for fifth-generation (5G) applications. Besides, achievement of duple negative (DNG) characteristics using a proposed compact complementary split-ring resonator (SRR), a broad epsilon negative metamaterial (ENG) with more than 1 GHz bandwidth (BW), and near-zero refractive index (NZRI) features are presented. The proposed mMIMO antenna consists of eight subarrays with three layers that operate in the 5G mind band at 3.5 GHz (3.40–3.65 GHz) with high port isolation between adjacent antenna elements compared to an antenna that does not use MTM. Each subarray has two patches on the top layer, while the middle and bottom layers have two categories of full and partial ground plans, respectively. Simulated, produced, and tested are 32 elements with a total volume of 184 × 340 × 1.575 mm3. The measured findings reveal that the sub-6 antenna has a better than 10 dB reflection coefficient (S11), a lower than 35 dB isolation, and a peak gain of 10.6 dBi for each subarray. Furthermore, the recommended antenna loaded with MTM has demonstrated good MIMO performance with an ECC of less than 0.0001, total efficiencies of more than 90%, more than 300 MHz bandwidth, and an overall gain of 19.5 dBi.