Throughput Improvement by Transmit 3D Beamforming and MCS Incorporating 1024-QAM

Three-dimensional beamforming (3D-BF) is a promising technique to improve user throughput and/or extend cell coverage in fifth-generation mobile systems. One of key technology for increasing data rates is the use of higher-order modulation such as 1024-quadrature amplitude modulation (QAM). In this paper, we evaluate the transmission performance of mobile networks that use a modulation and coding scheme (MCS) incorporating 1024-QAM and transmit 3D-BF. The average and 5-percentile user throughput are clarified as a function of the number of transmit (Tx) beams up to 24, using system-level computer simulations. From these results, we confirm that 3D-BF with 24 Tx beams can improve the average user throughput by 2.2 times compared with those of non-BF, however, the improvement effect exhibited a smaller increase in user throughput than the use of 16 Tx beams. We also confirm that 3D-BF with 24 Tx beams can increase the use rate of 1024-QAM in MCS by 17% when compared with non-BF. This work provides an effective solution for designing mobile systems using 1024-QAM and 3D-BF.