WLAN plays an important role as a complement to the existing or planned cellular networks which can offer high speed voice, video and data service up to the customer end. The aim of this paper is to analysis the performance of coded WLAN system for BPSK under AWGN channel. The low-density parity-check (LDPC) coding is considered as the high-performance channel coding scheme due to its good trad...

We analyze the effect of redundant parity-check equations on the error-floor performance of low-density paritycheck (LDPC) codes used over the additive white Gaussian noise (AWGN) channel. Our findings show that a large number of iterative decoding errors in the [2640, 1320] Margulis code, confined to point trapping sets in the standard Tanner graph, can be corrected if only one redundant parit...

Based on the ideas of cyclotomic cosets, idempotents and Mattson-Solomon polynomials, we present a new method to construct GF(2m ), where m > 0 cyclic low-density paritycheck codes. The construction method produces the dual code idempotent which is used to define the parity-check matrix of the low-density parity-check code. An interesting feature of this construction method is the ability to in...

This paper presents high-performance encoder and decoder architectures for a class of Low Density Parity Check (LDPC) codes. The codes considered here are based on the Parallelly Concatenated Parity Check encoder structure. A major advantage of these codes is that the generator matrix and the parity check matrix are both sparse, which leads to efficient VLSI implementations for the encoder and ...

We describe a novel approach to interpret a polar code as a low-density parity-check (LDPC)-like code with an underlying sparse decoding graph. This sparse graph is based on the encoding factor graph of polar codes and is suitable for conventional belief propagation (BP) decoding. We discuss several pruning techniques based on the check node decoder (CND) and variable node decoder (VND) update ...

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...

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...

This work explains the relationship between cycles, stopping sets, and dependent columns of the parity check matrix of low-density parity-check (LDPC) codes. Furthermore, it discusses how these structures limit LDPC code performance under belief propagation decoding. A new metric called extrinsic message degree (EMD) measures cycle connectivity in bipartite graphs. Using an easily computed esti...

We consider the decoding of convolutional codes using an error trellis constructed based on a submatrix of a given check matrix. In the proposed method, the syndromesubsequence computed using the remaining submatrix is utilized as auxiliary information for decoding. Then the ML error path is correctly decoded using the degenerate error trellis. We also show that the decoding complexity of the p...

In this paper Hard Decision and Soft Decision decoding techniques for Quasi-Cyclic-Low Density Parity Check (QC-LDPC) code and Low Density Parity Check (LDPC) code is introduced. QC-LDPC code is proposed to reduce the complexity of the Low Density Parity Check code while obtaining the similar performance. The decoding processes of these codes are easy to simplify and implement. The algorithms u...