A performance study of LTE MIMO-OFDM systems using the extended one-ring MIMO channel model

In this paper, we consider a long-term evolution (LTE) system for the downlink by using multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) techniques. The downlink channel is modeled by the socalled extended MIMO one-ring model. This model extends the well-known narrowband one-ring model with respect to frequency selectivity. The symbol error rate (SER) performance of the LTE MIMO-OFDM system is investigated for the downlink by employing different kinds of spatial encoders, where it is assumed that the channel state information (CSI) is perfectly known. For comparison, the space-time block coding (STBC) scheme, the vertical Bell Laboratories layered space-time (V-BLAST) scheme, and the space-frequency block coding (SFBC) scheme are all deployed in our performance study one by one. Simulation results show that an increase of the antenna element spacing at the evolved Node B (eNB) side has a greater effect than an increase of the antenna spacing by the same amount at the user equipment (UE) side. In addition, it turns out that the SFBC coding method offers a superior performance than the STBC scheme and significantly outperforms the V-BLAST approach under identical channel conditions.