A simple Sign-Bit Probabilistic Shaping Scheme

Vincent Corlay; Nicolas Gresset

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arXiv · 2109.15135

A simple Sign-Bit Probabilistic Shaping Scheme

Vincent Corlay·Nicolas Gresset

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Abstract

We propose a new shaping scheme for the Gaussian channel whose complexity is approximately half the one of a binary distribution matcher (DM). The result is obtained as follows: We first show that most of the shaping gain can be obtained via a simplified version of sign-bit shaping, which uses only two non-uniform binary sources. This is achieved by considering a stepwise Maxwell-Boltzmann-like distribution of the symbols. One of the two binary sources has a parameter $p$ close to 0. Hence, we then describe a binary DM which explicitly takes advantage of this aspect and has a negligible complexity. Since the two binary sources are used alternately with equal probability, the complexity of the proposed shaping scheme is half the one of the second binary DM.

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Vincent Corlay, Nicolas Gresset. 2021-09-30. A simple Sign-Bit Probabilistic Shaping Scheme. https://arxiv.org/abs/2109.15135

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