An Eight Element Wideband DGS MIMO Antenna System for 5G Handheld Devices

Abstract

In this article, a slotted wideband eight-element multiple-input multiple-output (MIMO) antenna system is designed for the N77 (3.3-4.2 GHz) spectrum. The MIMO system is fabricated FR-4 substrate with standard smartphone dimensions, The orthogonal placement of two element pairs at each corner ensure pattern and polarization diversity characteristics useful for signal reception in downlink and uplink conditions from various directions. The wideband performance, spanning 3.25-4.49 GHz according to criteria VSWR 2:1, is achieved by incorporating series-modified U-slots. Each MIMO element exhibits radiation and total efficiency exceeding 70%. An inter-element isolation of 14.5 dB is attained via a slot introduced along the PCB width. The design achieves an envelope correlation coefficient (ECC) below 0.02 and a diversity gain (DG) above 9.95 dB. Additionally, the Mean Effective Gain (MEG), Channel Capacity Loss (CCL), and Total Active Reflection Coefficient (TARC) are found to be within well-accepted limits. The MIMO system’s performance is also evaluated in single and dual-hand modes. S-parameters remain stable within the frequency range of 3.25-4.49 GHz, indicating robust performance under user influence. The developed prototype’s measurements agree well with simulations, indicating that the proposed MIMO system is a potential candidate for future 5G handheld devices.

Keywords

• Multi-input-multi-output (MIMO)
• 5G
• defected ground structure (DGS)
• ECC
• channel capacity loss (CCL)
• isolation