Low Density Parity Check (LDPC) codes have become very popular now-a-days because of their shannon limit approaching error correcting capability and hence have been used in many applications. This paper demonstrates a flexible Low Density Parity Check (LDPC) decoder which is an improve ment over other existing work on a general LDPC decoder. In this paper we have presented a fully flexible LDPC...

In this paper, we analyze the robustness for low-density parity-check (LDPC) codes over the Gilbert-Elliott (GE) channel. For this purpose we propose a density evolution method for the case where LDPC decoder uses the mismatched parameters for the GE channel. Using this method, we derive the region of tuples of true parameters and mismatched decoding parameters for the GE channel, where the dec...

•We observed that Low-Density ParityCheck (LDPC) codes based on partial geometries have superior performance to randomly constructed codes when decoded iteratively with the sum-product algorithm. •The reason for this good performance are redundant rows in the parity-check matrix. •We compared a parity-check matrix with redundant rows (Hredundant) with a matrix with full rank (Hfull) representin...

In this paper the low density party check (LDPC) codes used in the IEEE 802.16 standard physical layer are studied, and two novel techniques to enhance the performance of such codes are introduced. In the first technique, a novel parity check matrix for LDPC codes over GF(4) with the non-zero entries chosen to maximize the entropy is proposed, the parity check matrix is based on the binary pari...

Low Density Parity Check (LDPC) codes over GF(2) are an extension of binary LDPC codes that have not been studied extensively. Performances of GF(2) LDPC codes have been shown to be higher than binary LDPC codes, but the complexity of the encoders/decoders increases. Hence there is a substantial lack of hardware implementations for LDPC over GF(2) codes. This paper presents a FPGA serial implem...

Non-binary low-density parity check (NB-LDPC) codes are an extension of binary LDPC codes with significantly better performance. Although various kinds of low-complexity iterative decoding algorithms have been proposed, there is a big challenge for VLSI implementation of NBLDPC decoders due to its high complexity and long latency. In this brief, highly efficient check node processing scheme, wh...

This paper presents the construction of large girth Quasi-Cyclic low density parity check (QC-LDPC) codes. The row groups are paired two times the row weight which has cut down hardware implementation cost and complexity as compared to the connection of individual columns and rows. The construction of newly obtained codes gives a class of efficiently encodable quasi-cyclic LDPC codes.

Irregular Repeat-Accumulate (IRA) codes, introduced by Jin et al., have a linear-time encoding algorithm and their decoding performance is comparable to that of irregular low-density parity-check (LDPC) codes. Meanwhile the authors have introduced detailedly represented irregular LDPC code ensembles specified with joint degree distributions between variable nodes and check nodes. In this paper,...

Generalized quasi-cyclic (GQC) codes form a wide and useful class of linear codes that includes thoroughly quasi-cyclic codes, finite geometry (FG) low density parity check (LDPC) codes, and Hermitian codes. Although it is known that the systematic encoding of GQC codes is equivalent to the division algorithm in the theory of Gröbner basis of modules, there has been no algorithm that computes G...

The decoding of Low-Density Parity-Check (LDPC) codes is operated over a redundant structure known as the bipartite graph, meaning that the full set of bit nodes is not absolutely necessary for decoder convergence. In 2008, Soyjaudah and Catherine designed a recovery algorithm for LDPC codes based on this assumption and showed that the error-correcting performance of their codes outperformed co...