# Accession Number:

## AD0656783

# Title:

## RESEARCH TO DEVELOP THE ALGEBRAIC THEORY OF CODES

# Descriptive Note:

# Corporate Author:

## SYLVANIA ELECTRONIC SYSTEMS-EAST WALTHAM MA APPLIED RESEARCH LAB

# Personal Author(s):

# Report Date:

## 1967-06-01

# Pagination or Media Count:

## 84.0

# Abstract:

A number of new combinatorial designs are found as direct applications of the theory of error-correcting codes. Results on the automorphism groups of Hadamard matrices are presented. A simple proof of the well-known MacWilliams relations, together with a generalization, is given. We have constructed the 24, 12 extended code of Golay over GF2 in a particularly simple way. We prove that teach of the seven 6 2-15-36 designs v,k,lambda designs arising from the difference sets of size 15 in the Abelian groups of order 36 has only the obvious group as automorphism group. Each of these designs gives a Hadamard matrix of order 36. We determine the covering radius for BCH codes of design distance 2 over GFq for all odd prime powers q. We give two extensions of the Peterson-Kasami-Lin result on necessary and sufficient conditions for an extension of a cyclic code to be invariant under the affine group. Explicit factorizations of xto the lth power-1 over the appropriate quadratic-number field for l7, 11, 13, and 23 are given.

# Descriptors:

# Subject Categories:

- Cybernetics