A Variable Length Approach to Moment Balancing

Moment balancing templates have been proposed for channels with a small probability of an insertion/deletion (several orders smaller than additive errors) that add a minimal amount of redundancy. These templates are essentially a systematic way of encoding number-theoretic codes (primarily Levenshtein's s = 1 insertion/deletion code). Moment balancing templates proposed up to this point have been of fixed length. In this paper, it is shown that by using variable length templates, it is possible to obtain better performance than the optimal fixed length moment balancing template. Here, performance is defined as the amount of redundancy, which includes the moment balancing bits and the marker, that needs to be added.