Performance analysis of different MIMO transmission modes with link adaptation

In this paper, link adaptation, which dynamically selects modulation level and coding rate according to the channel condition, and several multi-input multi-output (MIMO) transmission modes are studied. As we know, the subchannels' signal-to-noise radio (SNR) by singular value decomposition (SVD) are unequal, which requires different modulation and coding schemes (MCS) to maximize the throughput. However, uniform channel decomposition (UCD) greatly reduces the coding and modulation complexity by decomposing the MIMO channel into multiple subchannels with identical capacity. This paper analyzes the post-detection SINR of different MIMO transmission modes and presents their throughput performance with link adaptation under the constraint of required packet error rate (PER). We show that UCD mode is the first choice at high SNR considering both coding/modulation complexity and throughput performance, while at low SNR, space-time block coding (STBC) mode outperforms other MIMO transmission modes.