Single-User MIMO for LTE-A Uplink: Performance Evaluation of OFDMA vs. SC-FDMA

The 3rd Generation Partnership Project (3GPP) Long Term Evolution-Advanced (LTE-A) aims at very high peak data rates such as 1 Gbps in local areas and 100 Mbps in wide areas. To meet these targets, evolved multi-antenna techniques and large spectrum allocations are required. In this paper, we carry out a performance evaluation of uplink single-user multiple-input-multiple-output (SU-MIMO), both for orthogonal frequency division multiple access (OFDMA) and single-carrier frequency division multiple access (SC-FDMA) under LTE parameters. Different MIMO schemes such as single-input-multiple-output (SIMO), spatial multiplexing (SM) and transmit diversity with space-frequency coding (SFC) are investigated. Results show that OFDMA tends to outperform SC-FDMA for 2 receive antennas. However, this gap is reduced when 4 antennas are considered at the receiver. Furthermore, it is shown that the peak-to-average power ratio (PAPR) of the SC-FDMA signal is increased about 0.6 dB, when SFC is employed; nevertheless, a gain of 2 dB over OFDMA is still preserved.