Methodology for Mode Selection in MIMO-OFDM System

Mode selection problem in MIMO-OFDM system is addressed. A general formulation is introduced to decompose the problem into two decoupled sub-problems: modulation and coding scheme (MCS) selection, and space-time processing (STP) optimization, each of which can be tackled more systematically. Mode selection algorithms can then be developed using a channel quality indicator (CQI) metric. The methodology is illustrated using the platform of IEEE 802.11n. The qualities of multiple CQI metrics are compared in terms of "coherency" and their performances are evaluated in terms of system goodput. This has been shown that the metric we proposed outperforms the other metrics.