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arXiv · 1701.03764

The Velocity of the Decoding Wave for Spatially Coupled Codes on BMS Channels

Rafah El-Khatib·Nicolas Macris
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Abstract

We consider the dynamics of belief propagation decoding of spatially coupled Low-Density Parity-Check codes. It has been conjectured that after a short transient phase, the profile of "error probabilities" along the spatial direction of a spatially coupled code develops a uniquely-shaped wave-like solution that propagates with constant velocity v. Under this assumption, and for transmission over general Binary Memoryless Symmetric channels, we derive a formula for v. We also propose approximations that are simpler to compute and support our findings using numerical data.

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Rafah El-Khatib, Nicolas Macris. 2017-01-13. The Velocity of the Decoding Wave for Spatially Coupled Codes on BMS Channels. https://arxiv.org/abs/1701.03764

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