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Suppose Q is a family of discrete memoryless channels. An unknown member of Q will be available, with perfect, causal output feedback for communication. Is there a coding scheme (possibly with variable transmission time) that can achieve the Burnashev erro ...
In this paper we describe some practical aspects of the design process of good Raptor codes for finite block lengths over arbitrary binary input symmetric channels. In particular we introduce a simple model for the finite-length convergence behavior of the ...
We prove that for any given R between 0 and 1 the best threshold value for a regular LDPC code of rate R with common variable degree v and common check degree c occurs when v is at least 3 and is minimal subject to the condition R=1−v/c ...
We show that the finite-length scaling parameters for irregular LDPC codes when used over the binary erasure channel can be computed without resorting to ``covariance evolution''. We provide simple expressions that can be evaluated using solely the degree ...
In this paper a class of discretized piecewise linear chaotic maps of a very high dimensions are used for communication over a noisy channel. An information payload that is sent over a channel is controlled in the transmitter and is related to the symbolic ...
Varaiya and Walrand found an elegant insight regarding the use of feedback in a causal coding context: While generally useful, feedback becomes useless when the channel is sufficiently symmetric. The goal of this note is to extend this insight to scenarios ...
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We consider communication over a time-invariant discrete memoryless channel (DMC) with noiseless and instantaneous feedback. We assume that the transmitter and the receiver are not aware of the underlying channel, however, they know that it belongs to some ...
We derive the average weight distribution function and its asymptotic growth rate for low-density parity-check (LDPC) code ensembles. We show that the growth rate of the minimum distance of LDPC codes depends only on the degree distribution pair. It turns ...
Burnashev in 1976 gave an exact expression for the reliability function of a discrete memoryless channel (DMC) with noiseless feedback. A coding scheme that achieves this exponent needs, in general, to know the statistics of the channel. Suppose now that t ...
We outline a procedure for using pseudorandom generators to construct binary codes with good properties, assuming the existence of sufficiently hard functions. Specifically, we give a polynomial time algorithm, which for every integers n and k, constru ...
