Although 5G era has come, the comprehensive coverage of 5G will take a long time for the vast number of underdeveloped countries and regions. Therefore, it is still significant to improve the depth coverage of 4G network. Massive Multi‐in Multi‐out (MIMO) is an application of 5G key technology in 4G network. In this study, based on the theoretical principle of beamforming, a special beamforming was realized by combining precoding and direction‐of‐arrival (DOA) estimation of sounding reference signal (SRS) in Massive MIMO antenna. Moreover, this beamforming antenna was applied to the existing 4G network. The building of deep coverage between indoor distribution and beamforming antenna was compared. It found that beamforming antenna can gain 6–8 dB beamforming gains and the overage coverage effect is better than indoor distribution. © 2020 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

中文翻译：

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基于5G中大规模MIMO波束成形的4G网络深度覆盖

尽管5G时代已经来临，但对于广大的不发达国家和地区来说，5G的全面覆盖将需要很长时间。因此，提高4G网络的深度覆盖仍然具有重要意义。大规模多进多出（MIMO）是5G关键技术在4G网络中的一种应用。在这项研究中，基于波束成形的理论原理，通过在Massive MIMO天线中结合预编码和到达参考信号（SRS）的到达方向（DOA）估计来实现特殊的波束成形。此外，该波束成形天线已应用于现有的4G网络。比较了室内分布和波束成形天线之间的深度覆盖范围。研究发现，波束成形天线可以获得6–8 dB的波束成形增益，并且覆盖范围大于室内分布。©2020日本电气工程师学会。由Wiley Periodicals LLC发布。