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arXiv · 1809.04037

Bit-Metric Decoding of Non-Binary LDPC Codes with Probabilistic Amplitude Shaping

Fabian Steiner·Georg Böcherer·Gianluigi Liva
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Abstract

A new approach for combining non-binary low-density parity-check (NB-LDPC) codes with higher-order modulation and probabilistic amplitude shaping (PAS) is presented. Instead of symbol-metric decoding (SMD), a bit-metric decoder (BMD) is used so that matching the field order of the non-binary code to the constellation size is not needed, which increases the flexibility of the coding scheme. Information rates, density evolution thresholds and finite-length simulations show that the flexibility comes at no loss of performance if PAS is used.

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Fabian Steiner, Georg Böcherer, Gianluigi Liva. 2018-09-11. Bit-Metric Decoding of Non-Binary LDPC Codes with Probabilistic Amplitude Shaping. https://doi.org/10.1109/lcomm.2018.2870180

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