Comparative Investigation on MU-MIMO Schemes for TDD MIMO OFDMA Uplink

CSI can be utilized at the transmitter to implement close loop multiuser MIMO and obtain both full spatial multiplexing and multiuser diversity gain in uplink. In this paper, multiuser per antenna rate control (MU-PARC) and multiuser singular value decomposition (MU-SVD) for spatial division multiplexing (SDM) of MIMO OFDM are investigated and a novel joint spatial frequency proportional fairness (PF) scheduling is proposed to guarantee the user fairness. MU-SVD is expected to achieve better system throughput since it can achieve full transmission and reception diversity and multiuser diversity gain, while MU-PARC can only achieve reception diversity and multiuser diversity gain. From the simulation results, the throughput of MU-SVD is 31% higher than that of MU-PARC for 4times2 MIMO and 8times4 MIMO scenario when SNR at receiver antenna is set as 10 dB without path loss and shadowing