Outdoor DL MU-MIMO and Inter Access Point Coordination Performance of Low-SHF-Band C-RAN Massive MIMO System for 5G

摘要

This paper describes our activities related to massive multi input and multi output (MIMO) for use in 5G radio access network (RAN). To achieve capacity enhancement and low power consumption, Massive MIMO has drawn attention as a key technology. Our research focuses on utilizing Massive MIMO in the low super-high-frequency (SHF) band, which is expected to be used for 5G commercial bands relatively soon, and on enhancing spectrum efficiency by spatial multiplexing with a low-SHF-band Massive MIMO antenna. The present work introduces a prototype low-SHF-band Centralized-RAN (C-RAN) Massive MIMO System including a low-SHF-band Massive MIMO active antenna system (AAS) that has 64 antenna elements, reports on outdoor downlink (DL) multi-user (MU) MIMO and inter access point (AP) coordination evaluations with the prototype system, and presents the results of the evaluations. The results demonstrate that the prototype low-SHF-band C-RAN Massive MIMO system can increase RAN system capacity and improve cell edge performance.