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In this study, a new method for constructing low-density parity-check (LDPC) codes is presented. This construction is based on permutation matrices which come from a finite abstract group and hence the codes constructed in this manner are called group permutation low-density parity-check (GP-LDPC) codes. A necessary and sufficient condition under which a GP-LDPC code has a cycle, is given and s...

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We introduce a computational technique that accurately predicts performance for a given LDPC code in the error floor region. We present some results obtained by applying the technique and describe certain aspects of it.

We propose a new decoding algorithm of LDPC codes over the binary erasure channel (BEC). The proposed decoding algorithm is an iterative one which uses the sparseness structure of the parity-check matrix of LDPC codes. We show by simulation results that the proposed decoding algorithm and the conventional decoding algorithm have a trade-off between remaining erasure rate and complexity. Keyword...

OF THE DISSERTATION Absorbing Set Analysis of LDPC Codes and Read-Channel Quantization in Flash Memory