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arXiv · 1701.03759

The Velocity of the Propagating Wave for General Coupled Scalar Systems

Rafah El-Khatib·Nicolas Macris
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Abstract

We consider spatially coupled systems governed by a set of scalar density evolution equations. Such equations track the behavior of message-passing algorithms used, for example, in coding, sparse sensing, or constraint-satisfaction problems. Assuming that the "profile" describing the average state of the algorithm exhibits a solitonic wave-like behavior after initial transient iterations, we derive a formula for the propagation velocity of the wave. We illustrate the formula with two applications, namely Generalized LDPC codes and compressive sensing.

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Rafah El-Khatib, Nicolas Macris. 2017-01-13. The Velocity of the Propagating Wave for General Coupled Scalar Systems. https://arxiv.org/abs/1701.03759

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