Accession Number : AD0704650

Title :   ON THE EQUIVALENCE OF FREE DISTANCE AND COLUMN DISTANCE OF A CONVOLUTIONAL CODE,

Corporate Author : ILLINOIS UNIV URBANA COORDINATED SCIENCE LAB

Personal Author(s) : Bell,Frank Ellwood , III

Report Date : APR 1970

Pagination or Media Count : 40

Abstract : A brief discussion of the role of coding theory in a communications system is followed by a description of convolutional codes and various distances measures. Two theorems and several corollaries concerning free distance are presented. The first theorem is essentially a correction of a counterexample to a conjecture relating free distance and column distance. The second demonstrates a necessary and sufficient condition for the free distance of a canonic systematic code to equal its order M' column distance. A corollary shows that the condition is a sufficient one for a nonsystematic code also. Two expressions for the probability of undetectable error of a specific code are presented. (Author)

Descriptors :   (*CODING, THEOREMS), PULSE TRANSMITTERS, DECODING, ERRORS

Subject Categories : Cybernetics

Distribution Statement : APPROVED FOR PUBLIC RELEASE