MacWilliams Identities for Codes on Graphs
Forney, David Golding · arXiv (Cornell University) · 2009
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.