Informed Dynamic Scheduling for Belief-Propagation Decoding of LDPC Codes

— Low-Density Parity-Check (LDPC) codes are usually decoded by running an iterative belief-propagation, or message-passing, algorithm over the factor graph of the code. The traditional message-passing schedule consists of updating all the variable nodes in the graph, using the same pre-update information, followed by updating all the check nodes of the graph, again, using the same pre-update information. Recently several studies show that sequential scheduling, in which messages are generated using the latest available information, significantly improves the convergence speed in terms of number of iterations. Sequential scheduling raises the problem of finding the best sequence of message updates. This paper presents practical scheduling strategies that use the value of the messages in the graph to find the next message to be updated. Simulation results show that these informed update sequences require significantly fewer iterations than standard sequential schedules. Furthermore...

• Type: Conference
• Year: 2007
• Where: ICC
• Authors: Andres I. Vila Casado, Miguel Griot, Richard D. Wesel
• Keywords: Communications, Factor Graph, ICC 2007, Sequential Scheduling, Traditional Message-passing Schedule