In this paper, we consider a class of column-weight two quasi-cyclic low-density parity check codes in which the girth can be large enough, as an arbitrary multiple of 8. Then we devote a convolutional form to these codes, such that their generator matrix can be obtained by elementary row and column operations on the parity-check matrix. Finally, we show that the free distance of the convolutio...

In recent years there has been a great deal of interest in R-parity violating supersymmetric models. We explain the motivation for studying these models and explore the various phenomenological consequences of R-parity violation. In particular, we argue that if we are to explore all channels for the discovery of supersymmetry then these models must be investigated. It has become essential for t...

HERWIG is a general-purpose Monte Carlo event generator, which includes the simulation of hard lepton-lepton, lepton-hadron and hadron-hadron scattering and soft hadron-hadron collisions in one package. It uses the parton-shower approach for initialand nal-state QCD radiation, including colour coherence e ects and azimuthal correlations both within and between jets. This article updates the des...

A class of one-dimensional convolutional codes will be presented. They are all MDS codes, i. e., have the largest distance among all one-dimensional codes of the same length n and overall constraint length δ. Furthermore, their extended row distances are computed, and they increase with slope n − δ. In certain cases of the algebraic parameters, we will also derive parity check matrices of Vande...

The celebrated Feng-Rao bound estimates the minimum distance of codes defined by means of their parity check matrices. From the Feng-Rao bound it is clear how to improve a large family of codes by leaving out certain rows in their parity check matrices. In this paper we derive a simple lower bound on the minimum distance of codes defined by means of their generator matrices. From our bound it i...

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 ...

In this paper1, we present a new pseudo-random sequence generator, constructed by using two ternary linear feedback shift registers (LFSR). This new generator is called an editing generator which is a combined model of the clock-control generator (viewed as insertion) and the shrinking generator (viewed as deletion). It is shown that the editing generator has good properties of randomness, such...