A Dual-Band Planar Antenna Array With High-Frequency Ratio for Both Sub-6 Band and mm-Waveband

Abstract

In the 3 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rd</sup> Generation Partnership Project (3GPP), the major carrier frequency bands of the 5G communication are assigned in the Sub-6 band and the millimeter wave (MMW) band. The frequency ratio between the two bands is more than 4. Due to the contradiction between large element size in Sub-6 band and narrow element spacing in the MMW band, it is hard to design one antenna array to be used in both of the two carrier frequency bands especially for a miniaturized communication system. In this article, a novel dual-band planar antenna array is proposed to solve the contradiction by using recombining technology. The measured results show that the antenna array is able to satisfy the requirements of the two carrier bands. In the Sub-6 band, the antenna array scale is 4×4. The antenna array has an operating band of 4.5-6GHz with the array gain more than 12.9dBi. In ±40° beam scanning angle, the sidelobe level (SLL) is lower than -12dB and the gain variation is less than ±0.9dBi. The isolation between the adjacent elements is more than 20 dB. In the MMW band, the array scale is 4×8. The antenna array has an operating band of 24.5-26GHz with the array gain more than 20dBi. In ±40° beam scanning angle, the SLL is lower than -10dB and the gain variation is less than ±1.9dBi. The isolation between the adjacent elements is more than 20dB. The antenna array has also shown good performance in an actual over air communication test in the two carrier bands by using 16-QAM modulation.