Impact of CSIT on the tradeoff of diversity and spatial multiplexing in MIMO channels

In this paper, we investigate the impact of imperfect channel state information at the transmitter (CSIT) on the fundamental tradeoff of diversity and multiplexing in multi-input multi-output (MIMO) fading channels. We show that through power adaptation, a higher diversity gain as well as a more efficient diversity-multiplexing tradeoff can be achieved than the reported results in literature. Our analysis reveals that imperfect CSIT significantly improves the achievable diversity gain while enjoying the full spatial multiplexing gain.