  An extension of the popular diversity-multiplexing tradeoff framework to the
low-SNR (or wideband) regime is proposed. The concept of diversity gain is
shown to be redundant in this regime since the outage probability is
SNR-independent and depends on the multiplexing gain and the channel power gain
statistics only. The outage probability under the DMT framework is obtained in
an explicit, closed form for a broad class of channels. The low and high-SNR
regime boundaries are explicitly determined for the scalar Rayleigh-fading
channel, indicating a significant limitation of the SNR-asymptotic DMT when the
multiplexing gain is small.
