Maximal and variable word-length comma-free codes

This paper explores the relationship between variable word-length synchronizable codes and comma-free codes. A simple construction procedure for comma-free codes of maximum dictionary size is presented. The concept of comma freedom is then reformulated to include the possibility of variable word length and two construction procedures for variable word-length comma-free codes are given. The resultant codes allow transmission of information at a higher rate than fixed word-length comma-free codes, for the same maximum synchronization delay.