Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: New Constructions of Codes for Asymmetric Channels via Concatenation   We present new constructions of codes for asymmetric channels for both binary
and nonbinary alphabets, based on methods of generalized code concatenation.
For the binary asymmetric channel, our methods construct nonlinear
single-error-correcting codes from ternary outer codes. We show that some of
the Varshamov-Tenengol'ts-Constantin-Rao codes, a class of binary nonlinear
codes for this channel, have a nice structure when viewed as ternary codes. In
many cases, our ternary construction yields even better codes. For the
nonbinary asymmetric channel, our methods construct linear codes for many
lengths and distances which are superior to the linear codes of the same length
capable of correcting the same number of symmetric errors.
  In the binary case, Varshamov has shown that almost all good linear codes for
the asymmetric channel are also good for the symmetric channel. Our results
indicate that Varshamov's argument does not extend to the nonbinary case, i.e.,
one can find better linear codes for asymmetric channels than for symmetric
ones.

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The categories of this paper are: hep-th
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The categories of this paper are: hep-ex
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The categories of this paper are: cond-mat
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The categories of this paper are: cmp-lg
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The categories of this paper are: nucl-ex
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The categories of this paper are: chem-ph
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The categories of this paper are: adap-org
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The categories of this paper are: alg-geom
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The categories of this paper are: bayes-an
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The categories of this paper are: q-fin
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The categories of this paper are: q-alg
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The categories of this paper are: plasm-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: funct-an
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The categories of this paper are: physics
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The categories of this paper are: ao-sci