Following the seminal work of Zheng and Tse on the diversity and multiplexing tradeoff (DMT) of MIMO channels, in this paper we introduce the array gain to further investigate the fundamental relation between transmission rate and reliability in MIMO systems. The array gain gives information on the power offset that results from exploiting channel state information at the transmitter or, simply, because of the channel model. Hence, the diversity, multiplexing, and array gain (DMA) tradeoff is able to cope with the limitations of the original DMT and provide with operational meaning in the sense that the DMA tradeoff of a particular system can be directly translated into a parameterized characterization of its associated outage probability performance. As a first step towards this objective, we present in this paper the fundamental DMA tradeoff achievable by any scheme in uncorrelated Rayleigh block-fading MIMO channels.

Peer Reviewed