Massachusetts Institute of Technology
The authors investigate the maximal achievable rate for a given block-length and error probability over quasi-static Single-Input Multiple-Output (SIMO) fading channels. Under mild conditions on the channel gains, it is shown that the channel dispersion is zero regardless of whether the fading realizations are available at the transmitter and/or the receiver. The result follows from computationally and analytically tractable converse and achievability bounds. Through numerical evaluation, they verify that, in some scenarios, zero dispersion indeed entails fast convergence to outage capacity as the block-length increases.