On the utility of a 3dB SNR gain in MIMO channels

In this paper, an outage limited MIMO channel is considered. We build on Zheng and Tse's elegant formulation of diversity-multiplexing tradeoff to develop a better understanding of the asymptotic relationship between probability of error, transmission rate and signal-to-noise ratio. We identify the limitation imposed by the notion of multiplexing gain and develop a new formulation for the throughput-reliability tradeoff that avoids this limitation. The new characterization is then used to shed more light on the asymptotic trends exhibited by the outage probability curves of MIMO channels.