Planar and compact multi-band MIMO antenna design for Wi-Fi and private 5G networks

The rapid progress of wireless communication demands higher data rates for end users. To meet this requirement, multiband operation and multiple-input multiple-output (MIMO) techniques with a greater number of antennas are essential for both Wi-Fi and 5G systems. This paper presents a compact planar tri-band antenna design that supports Wi-Fi at 2.4 GHz, the 5G n48 band for Citizens Broadband Radio Service (CBRS), and the 5G private network band (4.8–4.9 GHz). The antenna occupies a compact footprint of only 14 mm × 4.9 mm. The proposed design achieves a peak gain exceeding 2.2 dBi across all three operating bands, with simulated radiation efficiencies above 57%. These characteristics make the antenna highly suitable for MIMO configurations and spatial diversity applications.