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This thesis addresses the topic of Low-Density Parity-Check (LDPC) code analysis, both asymptotically and for finite block lengths. Since in general it is a difficult problem to analyze individual code instances, ensemble averages are studied by following ...
We study coding over a class of two-user broadcast channels with additive white Gaussian noise and fading known at the receivers only. Joint decoding of low-density parity-check codes is analyzed. The message update rule at the mapping node linking the use ...
We give a short survey of several techniques to construct codes on GF(q) that approach the capacity of the q-ary symmetric channel. The q-ary symmetric channel represents the next level of difficulty after the binary erasure channel (BEC). Since the channe ...
We construct new families of error-correcting codes based on Gallager's (1973) low-density parity-check codes. We improve on Gallager's results by introducing irregular parity-check matrices and a new rigorous analysis of hard-decision decoding of these co ...
This paper starts a systematic study of capacity-achieving (c.a.) sequences of low-density parity-check codes for the erasure channel. We introduce a class A of analytic functions and develop a procedure to obtain degree distributions for the codes. We sho ...
In this paper we will survey some of the most recent results on low-density parity-check codes. Our emphasis will be primarily on the asymptotic theory of these codes. For the most part, we will introduce the main concepts for the easier case of the erasur ...
This paper investigates the use of algebraic-geometric codes for data transmission over a packet network, by comparing their encoding/decoding speeds to those of the ubiquitous Reed-Solomon Codes. We take advantage of the fact that AG codes allow the const ...
What makes a source–channel communication system optimal? It is shown that in order to achieve an optimal cost–distortion tradeoff, the source and the channel have to be matched in a probabilistic sense. The match (or lack of it) involves the source distri ...
Within the validation work of EGNOS for civil aviation, it is interesting to analyze the transmitted corrections individually. In this paper, the ionospheric model of EGNOS is compared to the one determined by an independent organization (CODE). The contin ...
We investigate the average erasure probability of the belief propagation algorithm over the binary erasure channel (BEC) for various finite-length low- density parity-check (LDPC) ensembles. In particular, we give tight upper bounds on the "error floor", i ...
