1. A Sphere-Packing Error Exponent for Mismatched Decoding
- Author
-
Ehsan Asadi Kangarshahi and Albert Guillén i Fàbregas
- Subjects
FOS: Computer and information sciences ,Information Theory (cs.IT) ,Computer Science - Information Theory ,Data_CODINGANDINFORMATIONTHEORY ,Library and Information Sciences ,Computer Science::Information Theory ,Computer Science Applications ,Information Systems - Abstract
We derive a sphere-packing error exponent for coded transmission over discrete memoryless channels with a fixed decoding metric. By studying the error probability of the code over an auxiliary channel, we find a lower bound to the probability of error of mismatched decoding. The bound is shown to decay exponentially for coding rates smaller than a new upper bound to the mismatch capacity which is established in this paper. For rates higher than the new upper bound, the error probability is shown to be bounded away from zero. The new upper bound is shown to improve over previous upper bounds to the mismatch capacity.
- Published
- 2023