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This paper extends the construction and analysis of Raptor codes originally designed in A. Shokrollahi (2004) for the erasure channel to general symmetric channels. We explicitly calculate the asymptotic fraction of output nodes of degree one and two for c ...
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 ...
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 ...
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 ...
This paper exhibits a class of universal Raptor codes: for a given integer k, and any real /spl epsiv/>0, Raptor codes in this class produce a potentially infinite stream of symbols such that any subset of symbols of size k(1 + /spl epsiv/) is sufficient t ...
This paper provides an efficient method for analyzing the error probability of the belief propagation (BP) decoder applied to LT Codes. Each output symbol is generated independently by sampling from a distribution and adding the input symbols corresponding ...
Transmission of packets over computer networks is subject to packet-level errors, which appear as "bursts" of bit-level errors and are not well modeled by memoryless binary channels. A standard scrambling technique is used for transmission of packets by th ...
We consider a multicast configuration with two sources, and translate the network code design problem to vertex coloring of an appropriately defined graph. This observation enables to derive code design algorithms and alphabet size bounds, as well as estab ...
Disclosed is a method for wireless signal transmission of signals from an array of two or more antennas, in which each signal to be transmitted is selected from a constellation of unitary space-time signals. Each unitary space-time signal is a unitary matr ...
This paper proposes a universal variable-length lossless compression algorithm based on fountain codes. The compressor concatenates the Burrows-Wheeler block sorting transform (BWT) with a fountain encoder, together with the closed-loop iterative doping al ...
