High Isolation MIMO Antenna System for 5G N77/N78/N79 Bands

Area of Science:

• Electrical Engineering
• Wireless Communications
• Antenna Theory

Background:

• Fifth-generation (5G) mobile terminals require advanced antenna systems for high-speed data transmission.
• Multiple-Input Multiple-Output (MIMO) antenna technology is crucial for enhancing spectral efficiency and link reliability in 5G networks.
• Achieving high isolation between closely spaced antenna elements in compact mobile devices presents a significant design challenge.

Purpose of the Study:

• To design and validate a symmetric dual-band MIMO antenna system for 5G mobile terminals.
• To operate effectively within the 5G N77/N78 (3.4-3.6 GHz) and N79 (4.8-5.0 GHz) frequency bands.
• To achieve high isolation between antenna elements to minimize interference and maximize system performance.

Main Methods:

• A symmetric dual-band MIMO antenna system was proposed, incorporating slotting and self-decoupling techniques for enhanced isolation.
• Antenna elements were designed with rectangular microstrip radiators and grounded rectangular rings, positioned on perpendicular frames relative to the smartphone's main board.
• The feed network was implemented on the main board, connecting to an external SMA connector at the board's base.

Main Results:

• The proposed MIMO antenna system demonstrated high isolation, exceeding 20 dB in the lower 5G band (N77/N78) and 24 dB in the higher band (N79).
• Measurement results showed excellent agreement with simulation outcomes, validating the antenna system's performance.
• The design successfully integrated antenna elements onto frames perpendicular to the main board, optimizing space utilization.

Conclusions:

• The developed symmetric dual-band MIMO antenna system is suitable for 5G mobile terminals, offering superior isolation and performance.
• The employed slotting and self-decoupling techniques effectively address the challenge of element isolation in compact 5G devices.
• The validated design provides a robust solution for enhancing 5G communication capabilities in mobile platforms.