Experimental evaluation on 5G radio access employing multi-user MIMO at 15 GHz band

This paper presents indoor and outdoor experimental results on the achievable throughput for downlink 8-by-16 multi user (MU)-multiple-input multiple-output (MIMO) using 2 sets of user equipment (UE) and carrier aggregation with 8 component carriers in various measurement areas for 5G radio access. In the presence of four centralized antenna units, the throughput performance is evaluated using the implemented 5G testbed for MU-MIMO operation. The experimental results show that the peak system throughput of 18.6 Gbps and 25.9 Gbps are achieved in indoor and outdoor environments. Furthermore, we confirm that to avoid interference a vertical angle exceeding 18 deg. or a horizontal angle exceeding 10.7 deg. is required between UEs to achieve the throughput of 12 Gbps for a UE when employing MU-MIMO in an outdoor open space.