Edge-based Scheduled BP in LDPC Codes

This paper studies the potential performance gain, referred to as scheduling gain, when decoding LDPC codes using scheduled belief-propagation. Introducing genie-aided scheduling, it is shown that the scheduling-gain can be quite impressive for moderate and short-length codes. Adaptive schedule based on edge ordering is presented. This approach compares favorably with serial scheduling schemes based on random node ordering. Density evolution-based analysis appropriately tailored for decoding finite-length LDPC codes is provided. For serial decoding and genie-aided decoding, it is shown that the performance in the first iteration can be accurately predicted analytically using the proposed technique.