1. NB QC-LDPC Coded QAM Signals with Optimized Mapping: Bounds and Simulation Results
- Author
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Bocharova, Irina E., Kudryashov, Boris D., Ovsyannikov, Evgenii P., and Skachek, Vitaly
- Subjects
Computer Science - Information Theory - Abstract
The goal of the paper is to study specific properties of nonbinary low-density parity-check (NB LDPC) codes when used in coded modulation systems. The paper is focused on the practically important NB LDPC codes over extensions of the Galois field GF$(2^m)$ with $m \le 6$ used with QAM signaling. Performance of NB QC LDPC coded transmission strongly depends on mapping of nonbinary symbols to signal constellation points. We obtain a random coding bound on the maximum-likelihood decoding error probability for an ensemble of random irregular NB LDPC codes used with QAM signaling for specific symbol-to-signal point mappings. This bound is based on the ensemble average Euclidean distance spectra derived for these mappings. The simulation results for the belief-propagation decoding in the coded modulation schemes with the NB quasi-cyclic (QC)-LDPC codes under different mappings are given. Comparisons with the optimized binary QC-LDPC codes in the WiFi and 5G standards, as well as with the new bound, are performed., Comment: arXiv admin note: text overlap with arXiv:2006.12147
- Published
- 2021