2009/03/24 by Forney, G. David
#FOS: Computer and information sciences #Information Theory (cs.IT)
paper · doi:10.48550/arxiv.0903.4207
The MacWilliams identity for linear time-invariant convolutional codes that has recently been found by Gluesing-Luerssen and Schneider is proved concisely, and generalized to arbitrary group codes on graphs. A similar development yields a short, transparent proof of the dual sum-product update rule.