This paper mainly about the study on one of the widely used error correcting codes that is Low parity check Codes (LDPC). In this paper, the Regular LDPC code has been discussed The LDPC codes explained in this paper is about the Regular Binary LDPC codes or the Gallager. Keywords—LDPC, channel coding.

Low Density Parity Check (LDPC) codes have attracted current researchers due to their excellent performance and capability of parallel decoding. One major criticism concerning LDPC codes has been their apparent high encoding complexity and memory inefficient nature due to large parity check matrix. This led the researchers to move into a memory efficient LDPC called Quasi-Cyclic (QC)-LDPC which...

Binary low-density parity-check (LDPC) codes perform very well on magnetic recording channels (MRCs) with additive white Gaussian noise (AWGN). However, an MRC is subject to other impairments, such as media defects and thermal asperities. Binary LDPC codes may not be able to cope with these impairments without the help of a Reed–Solomon code. A better form of coding may be -ary LDPC codes, whic...

In the framework of error correction in space telecommand (TC) links, Consultative Committee for Space Data Systems (CCSDS) currently recommends short block-length BCH and binary low-density parity-check (LDPC) codes. Other alternatives have been discarded due to their high decoding complexity, such as non-binary LDPC (NB-LDPC) NB-LDPC codes perform better than counterparts over AWGN jamming ch...

Low-density parity-check (LDPC) codes, invented by Gallager [2], who described and analyzed a block variant of the codes, arouse great interest of researchers. These codes are widely used in practice since they can be decoded by using relatively simple iterative decoding algorithms. Several modifications of these codes are known, in particular, generalized LDPC codes [3]. In contrast to Gallage...

A specific LDPC check matrix structure is used to form multi-channel alternative signal to solve the problem that traditional block codes inhibiting PAPR scheme is not suitable for a large number of sub-carriers and LDPC code is applied to the field of optimization of peak-to-average ratio. A rapid construction method of LDPC check matrix and fast encoding process using matrix are analyzed in d...

ETRI Journal, Volume 28, Number 5, October 2006 ABSTRACT⎯The effect of block interleaving in a low density parity check (LDPC)-turbo concatenated code is investigated in this letter. Soft decoding can be used in an LDPC code unlike the conventional Reed-Solomon (RS) code. Thus, an LDPC-turbo concatenated code can show better performance than the conventional RS-turbo concatenated code. Furtherm...

In this paper, we suggest a new technique for LDPC parity-check matrix (H-matrix) generation and a corresponding decoding process. The key idea is to construct LDPC H-matrix by using a convolutional encoder. It is easy to have many different coderates from a mother code with convolutional codes. However, it is difficult to have many different coderates with LDPC codes. Constructing LDPC Hmatrix...

This paper presents a study on the VHDL implementation of a class of binary irregular structured LDPC codes (IS-LDPC) applied to 100 Gbps optical networks. A comparison between two iterative decoding algorithms for irregular structured LDPC codes, sum-product based on loglikelihood ratio and min-sum, is used to define the best choice for implementation. The performances of IS-LDPC codes are eva...

This paper is the second part of a series of two papers on the investigation of the connection between two methods for constructing LDPC codes, namely the superposition and the protograph-based methods. In the first part, by taking the graph point of view, we established a strong connection between these two construction methods and showed that, in the binary case, the protograph-based construc...