Codes and their decoding March 2010
نویسنده
چکیده
In this lecture, we shall look at Expander Codes, Tanner Codes which are a generalization of Expander Codes and Distance amplification codes. These codes visualize the code as a graph where the value of the ith bit of a codeword corresponds to, for example, the value associated with the ith vertex or the ith edge of the graph. The properties of the graph determine the properties such as distance and efficient decodability of the code. Further, the constraints such as parity checks put on the codewords manifest as local constraints on vertices or edges such as constraints on the set of the values the edges incident to a vertex can take.
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