Limits RegistryPUBLIC RECORD
Limits RegistryIn a landmark 2001 IEEE Transactions on Information Theory paper, Chung, Forney, Richardson, and Urbanke designed an irregular low-density parity-check (LDPC) code that operates within 0.0045 dB of the Shannon limit for the binary-input AWGN channel — a gap that was, at the time, the closest any practical, decodable code had come to Shannon's theoretical ceiling. This result helped establish LDPC codes as a practical near-capacity-achieving technology, now used in Wi-Fi, 5G, and satellite standards.
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In a landmark 2001 IEEE Transactions on Information Theory paper, Chung, Forney, Richardson, and Urbanke designed an irregular low-density parity-check (LDPC) code that operates within 0.0045 dB of the Shannon limit for the binary-input AWGN channel — a gap that was, at the time, the closest any practical, decodable code had come to Shannon's theoretical ceiling. This result helped establish LDPC codes as a practical near-capacity-achieving technology, now used in Wi-Fi, 5G, and satellite standards.
The smallest published gap, in required signal-to-noise ratio, between an irregular low-density parity-check code's performance and the Shannon channel-capacity limit for the binary-input additive white Gaussian noise channel.
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1 accepted Claim, with 1 linked evidence records.
Permanent ID limitsregistry.com/limits/LR-LDPC-NEAR-SHANNON-LIMIT
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Limits Registry. LR-LDPC-NEAR-SHANNON-LIMIT. Closest approach to the Shannon limit by a practical error-correcting code. 2026.