Fifth‐generation mobile communications systems now being developed use antennas with large numbers of antenna elements and are decided to be massive‐MIMO technologies for flexibly changing the antenna beam (beam forming). Obtaining the required directivity for a multielement antenna requires control of the phase and amplitude of the variable phase shifter and variable amplifier built into each antenna element. Moreover, the variable phase shifter and variable gain amplifier settings must be obtained so that every antenna element radiates equiamplitude and equiphase radio waves. This process is called antenna calibration. This paper proposes a method using near‐field measurement and back‐projection processing to perform calibration. Moreover, actual calibration tests of a simulated massive‐MIMO base station were executed using the proposed method. The results reported here confirm that calibration can be implemented using the proposed method even when the phase shifter of the simulated base station suffers large variability. © 2020 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

中文翻译：

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拟议的使用近场测量的MIMO天线校准方法

现在正在开发的第五代移动通信系统使用带有大量天线元件的天线，因此被确定为大规模MIMO技术，可以灵活地改变天线波束（波束形成）。为了获得多元件天线所需的方向性，需要控制内置在每个天线元件中的可变移相器和可变放大器的相位和幅度。而且，必须获得可变移相器和可变增益放大器的设置，以使每个天线元件都辐射等幅和等相无线电波。此过程称为天线校准。本文提出了一种使用近场测量和反投影处理进行校准的方法。此外，使用所提出的方法执行了模拟大规模MIMO基站的实际校准测试。此处报告的结果证实，即使模拟基站的移相器具有较大的可变性，也可以使用建议的方法来执行校准。©2020日本电气工程师学会。由Wiley Periodicals LLC发布。