7 research outputs found
Refinement of the random coding bound
An improved pre-factor for the random coding bound is proved. Specifically,
for channels with critical rate not equal to capacity, if a regularity
condition is satisfied (resp. not satisfied), then for any a
pre-factor of (resp. ) is achievable for rates above the
critical rate, where and is the blocklength and rate, respectively. The
extra term is related to the slope of the random coding
exponent. Further, the relation of these bounds with the authors' recent
refinement of the sphere-packing bound, as well as the pre-factor for the
random coding bound below the critical rate, is discussed.Comment: Submitted to IEEE Trans. Inform. Theor