volume | PIER Journals

Abstract

This paper proposes a broadband multi-input multi-output (MIMO) antenna array operating in the 3.3-6 GHz frequency range. The antenna array consists of eight identical Z-shaped radiation elements, and the coupling between the antenna elements is minimized through the use of an optimized defected ground structure. Each antenna element is composed of a modified Z-shaped radiation strip, an opposing L-shaped strip, and a rectangular strip. Based on simulation and measurement results, it can be concluded that the antenna array meets the -10 dB bandwidth requirement within the desired frequency band, with the transmission coefficient of less than -15 dB, and an envelope correlation coefficient (ECC) below 0.006. Additionally, the proposed antenna achieves a maximum gain ranging from 2.6-8 dBi, with an efficiency exceeding 76%. The overall size of the phone antenna is 150 × 75 × 7 mm³, while each antenna element measured only 7.8 mm × 7 mm × 0.8 mm (0.091λ × 0.082λ × 0.009λ, where λ represents the wavelength at 3.5 GHz). The high-isolation broadband MIMO antenna proposed in this study emerges as a promising candidate for fifth-generation (5G) New Radio (NR) and WLAN applications.

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Dr. Juhui Zhang

Dr. Wei Luo

Dr. Qiangjuan Li

Dr. Yuexiao Pan

Professor Gui Liu