In communication through asymmetric channels the capacity-achieving input
distribution is not uniform in general. Homophonic coding is a framework to
invertibly convert a (usually uniform) message into a sequence with some target
distribution, and is a promising candidate to generate codewords with the
nonuniform target distribution for asymmetric channels. In particular, a
Variable-to-Fixed length (VF) homophonic code can be used as a suitable
component for channel codes to avoid decoding error propagation. However, the
existing VF homophonic code requires the knowledge of the maximum relative gap
of probabilities between two adjacent sequences beforehand, which is an
unrealistic assumption for long block codes. In this paper we propose a new VF
homophonic code without such a requirement by allowing one-symbol decoding
delay. We evaluate this code theoretically and experimentally to verify its
asymptotic optimality.Comment: Full version of the paper to appear in 2017 IEEE International
Symposium on Information Theory (ISIT2017