Low-density parity check ( LDPC ) codes : A new era in coding
Hashneet Kaur2015
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Abstract
Low Density comes from the characteristic of their parity-check matrix that contains small number of 1s in comparison to the amount of 0s in them. This sparseness of parity check matrix guarantees two features: First, a decoding complexity which increases only linearly with the code length and second, a minimum distance which also increases linearly with the code length. These codes are practical implementation of Shannon noisy coding theorem[1]. LDPC codes are similar to other linear block codes. Actually, every existing code can be successfully implemented with the LDPC iterative decodSukhleen Bindra Narang, Kunal Pubby*, Hashneet Kaur Department of Electronics Technology, Guru Nanak Dev University, Amritsar, (INDIA) E-mail: [email protected]
Key takeaways
- LDPC codes offer both better performance and lower decoding complexity.
- Indeed, the decoding algorithm of turbo codes was subsequently shown to be a special case of that for LDPC codes presented by Gallager so many years before.
- LDPC codes refer to the class of block codes where the percentage of 1's in the parity check matrix is low.
- Fan showed that a specific class of codes Array codes can be viewed as LDPC codes and can be decoded using message passing algorithm.
- Implementation of LDPC codes has lagged behind implementations of other codes, importantly that of turbo codes, Used with OFDM technology to achieve low error rate.
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