Accession Number : AD0474482

Title :   REINFORCED PREFIXED COMMA FREE CODES.

Descriptive Note : Interim technical rept.,

Corporate Author : HARVARD UNIV CAMBRIDGE MA CRUFT LAB

Personal Author(s) : Ramamoorthy, C. V. ; Tufts, D. W.

Report Date : AUG 1965

Pagination or Media Count : 26

Abstract : A new class of prefixed comma free codes is considered in which the distance between the prefix of length A and other A-tuple is allowed to vary with the position of the A-tuple. This is particularly useful for systems in which the receiver can predict the position of the synchronizing prefix within a number of digits that is small compared to the work length. This work extends the work of Gilbert, who has considered uniform, distance one, prefixed comma free codes. Our generalization of the constraints on comma free codes leads us to modifications of Gilbert's method of enumerating the number of allowable code words. By treating the state diagram of a code word generator as a signal flow graph the enumeration can be performed by using the flowgraph loop rule developed by Shannon, Mason, and Lorens. (Author)

Descriptors :   (*CODING, SEQUENCES(MATHEMATICS)), AUTOMATA, INFORMATION THEORY, SEQUENCES(MATHEMATICS), MATRICES(MATHEMATICS).

Subject Categories : Cybernetics

Distribution Statement : APPROVED FOR PUBLIC RELEASE