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The new 5G communications standard increases data rates and supports low-latency communication that places constraints on the computational complexity of channel decoders. 5G low-density parity-check (LDPC) codes have the so-called protograph-based raptor-like (PBRL) structure which offers inherent rate-compatibility and excellent performance. Practical LDPC decoder implementations use message-passing decoding with finite precision, which becomes coarse as complexity is more severely constrained. Performance degrades as the precision becomes more coarse. Recently, the information bottleneck (IB) method was used to design mutual-information-maximizing lookup tables that replace conventional finite-precision node computations. The IB approach exchanges messages represented by integers with very small bit width. This paper extends the IB principle to the flexible class of PBRL LDPC codes as standardized in 5G. The extensions include puncturing and rate-compatible IB decoder design. As an example of the new approach, a 4-bit information bottleneck decoder is evaluated for PBRL LDPC codes over a typical range of rates. Frame error rate simulations show that the proposed scheme outperforms offset min-sum decoding algorithms and operates very close to double-precision sum-product belief propagation decoding.
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LDPC decoders with re-initializations based on synergy of hard decision and message passing principles
In this paper we propose the approaches that combine two types of iterative decoding algorithms that are usually used for decoding of low density parity check codes (LDPC). One strategy is based on a low-complexity bit-flipping algorithm, and the proposed modification enable significant performance improvement, with no significant increase of the average computing complexity. The other strategy is based on belief propagation decoder, and the resulting decoder has improved error correction capabilities for the codes with short codeword length.
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- PAR ID:
- 10342843
- Date Published:
- Journal Name:
- Conference on Electronics, Telecommunication, Computing, Automation and Nuclear Engineering
- Page Range / eLocation ID:
- 758 - 763
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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