Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Tree-Structure Expectation Propagation for LDPC Decoding in Erasure
  Channels   In this paper we present a new algorithm, denoted as TEP, to decode
low-density parity-check (LDPC) codes over the Binary Erasure Channel (BEC).
The TEP decoder is derived applying the expectation propagation (EP) algorithm
with a tree- structured approximation. Expectation Propagation (EP) is a
generalization to Belief Propagation (BP) in two ways. First, it can be used
with any exponential family distribution over the cliques in the graph. Second,
it can impose additional constraints on the marginal distributions. We use this
second property to impose pair-wise marginal constraints in some check nodes of
the LDPC code's Tanner graph. The algorithm has the same computational
complexity than BP, but it can decode a higher fraction of errors when applied
over the BEC. In this paper, we focus on the asymptotic performance of the TEP
decoder, as the block size tends to infinity. We describe the TEP decoder by a
set of differential equations that represents the residual graph evolution
during the decoding process. The solution of these equations yields the
capacity of this decoder for a given LDPC ensemble over the BEC. We show that
the achieved capacity with the TEP is higher than the BP capacity, at the same
computational complexity.

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The categories of this paper are: eess
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The categories of this paper are: patt-sol
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The categories of this paper are: hep-th
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: bayes-an
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The categories of this paper are: funct-an
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The categories of this paper are: math-ph
3
The categories of this paper are: physics
32
The categories of this paper are: atom-ph
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The categories of this paper are: nlin
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The categories of this paper are: stat
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The categories of this paper are: q-bio
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The categories of this paper are: chao-dyn
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The categories of this paper are: dg-ga
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The categories of this paper are: alg-geom