A dual-band four-port MIMO antenna with a partial ground plane for n257/n260/n261 band applications

Abstract

Abstract In this paper, a compact four-port dual-band multiple-input-multiple-output (MIMO) antenna is designed and developed for fifth-generation (5G) millimeter-wave applications. The proposed antenna operates in the n257 band at 28 GHz and the n260/n261 bands at 38 GHz within the 5G new radio (NR) frequency range-2 (FR2) spectrum, thereby supporting enhanced data rates, high capacity, and low-latency applications. The dual-band unit element of the proposed 4-port MIMO antenna consists of a modified rectangular patch antenna with a partial ground plane. The modified patch structure is obtained by loading a microstrip-fed rectangular patch with H-shaped and inverted T-shaped slots. The unit elements are placed orthogonally to each other, and they are interconnected at the center via extended stubs. The designed dual-band MIMO antenna has an overall volume of 28 mm × 28 mm × 0.254 mm, which is approximately $$0.161{\varvec{\lambda}}_{0}^{3}$$ , where $${\varvec{\lambda}}_{0}$$ corresponds to the operating wavelength at 28 GHz. The designed MIMO antenna operates at 27.26–29.90 GHz and 37.57–40.29 GHz, which fall within the n257/n261 and n260 bands of the 5G NR FR2 spectrum, with inter-port isolation better than 20 dB across both bands. The proposed antenna system demonstrates excellent MIMO performance, validating its ability to support reliable, high-capacity, and low-latency communication, making it a strong candidate for next-generation 5G millimeter-wave applications .