Ultra-compact 4-port MIMO antenna with defected ground structure and SAR analysis for 28/38 GHz 5G mobile devices

• Main Authors: Al Gburi, Ahmed Jamal Abdullah, Elabd, Rania Hamdy
• Format: Article
• Language: English
• Published: Taylor and Francis Ltd. 2024
• Online Access: http://eprints.utem.edu.my/id/eprint/27431/2/0270230052024205356838.PDF; http://eprints.utem.edu.my/id/eprint/27431/; https://www.tandfonline.com/doi/abs/10.1080/09205071.2024.2354716

To tackle the challenge of keeping 5G mobile devices compact while supporting millimeter-wave bands, we've created an ultra-compact 4-port dual-band MIMO antenna with a defected ground structure (DGS). This design minimizes mutual coupling and covers a broad frequency range. Built on a Rogers TMM4 substrate with dimensions of 17.76×17.76 mm2, the antenna includes four planar patch antennas positioned perpendicularly at the corners. Each antenna operates at 28/38 GHz and features a rectangular patch with four rectangular slots and a full ground plane. The patches are separated by 0.5 λo, with the DGS further reducing mutual coupling. Both simulations and measurements indicate a significant reduction in mutual coupling (−39 to −60 dB), improving ECC, TARC, MEG, and DG. Time-domain and SAR analyses confirm the antenna's efficiency and its suitability for 5G devices.