Protograph-Based LDPC Code Design for Probabilistic Shaping with On-Off Keying

Alexandru Dominic Git; Balázs Matuz; Fabian Steiner

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arXiv · 1901.03285

Protograph-Based LDPC Code Design for Probabilistic Shaping with On-Off Keying

Alexandru Dominic Git·Balázs Matuz·Fabian Steiner

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Abstract

This work investigates protograph-based LDPC codes for the AWGN channel with OOK modulation. A non-uniform distribution of the OOK modulation symbols is considered to improve the power efficiency especially for low SNRs. To this end, a specific transmitter architecture based on time sharing is proposed that allows probabilistic shaping of (some) OOK modulation symbols. Tailored protograph-based LDPC code designs outperform standard schemes with uniform signaling and off-the-shelf codes by 1.1 dB for a transmission rate of 0.25 bits/channel use.

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Alexandru Dominic Git, Balázs Matuz, Fabian Steiner. 2019-01-10. Protograph-Based LDPC Code Design for Probabilistic Shaping with On-Off Keying. https://arxiv.org/abs/1901.03285

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