— In this paper, we investigate the encoding and decoding method of the irregular LDPC (Low Density Parity Check) codes that offer diverse coding rates from 1/2 to 9/10 defined in the Digital Video Broadcasting (DVB-S2) standard. We study the efficient memory assignment and the implementing method in the LDPC codes.

We consider user cooperation in a wireless relay network that comprises a collection of transmitters sending data to a common receiver through inherently unreliable and constantly changing channels. Exploiting the recently developed technology of network coding, we propose a new framework, termed adaptive network coded cooperation (ANCC), as a practical, de-centralized, adaptive and efficient c...

We propose a method to recover the structure of a randomly permuted chained code and how to cryptanalyse cryptographic schemes based on these kinds of error coding. As application of these methods is a cryptographic schema using regular Low Density Parity Check (LDPC) Codes. This result prohibits the use of chained code and particularly regular LDPC codes on cryptography.

Protograph low-density-parity-check (LDPC) are considered to design near-capacity lowrate codes over the binary erasure channel (BEC) and binary additive white Gaussian noise (BIAWGN) channel. For protographs with degree-one variable nodes and doubly-generalized LDPC (DGLDPC) codes, conditions are derived to ensure equality of bit-error threshold and block-error threshold. Using this condition,...

In this paper we design low-density parity-check (LDPC) codes for erasure channels with packet losses. Binary base matrices with good minimum stopping set size are designed and superposition is used with these matrices to construct LDPC codes which can correct losses of whole packets. By using superposition, rather than by using the more traditional codeword interleaving, LDPC codes are produce...

We introduce a new class of low-density parity-check (LDPC) codes constructed from a template called a protograph. The protograph serves as a blueprint for constructing LDPC codes of arbitrary size whose performance can be predicted by analyzing the protograph. We apply standard density evolution techniques to predict the performance of large protograph codes. Finally, we use a randomized searc...

An algebraic group ring method for constructing codes with no short cycles in the check matrix is derived. It is shown that the matrix of a group ring element has no short cycles if and only if the collection of group differences of this element has no repeats. When applied to elements in the group ring with small support this gives a general method for constructing and analysing low density pa...

The design of a class of well-structured low-density parity-check (LDPC) codes, namely linear interleaver based concatenated zigzag (LICZ) codes, is investigated. With summary distances as the design metric, short LICZ codes with large minimum distances can be constructed. Moreover, an efficient cycle-based method is proposed to compute the minimum distances of LICZ codes. Simulation results sh...

Abstract — Density evolution (DE) is one of the most powerful analytical tools for low-density parity-check (LDPC) codes on memoryless binaryinput/symmetric-output channels. The case of nonsymmetric channels is tackled either by the LDPC coset code ensemble (a channel symmetrizing argument) or by the generalized DE for linear codes on non-symmetric channels. Existing simulations show that the b...

Density evolution (DE) is one of the most powerful analytical tools for low-density parity-check (LDPC) codes on memoryless binary-input/symmetric-output channels. The case of non-symmetric channels is tackled either by the LDPC coset code ensemble (a channel symmetrizing argument) or by the generalized DE for linear codes on non-symmetric channels. Existing simulations show that the performanc...