High Girth Column-Weight-Two LDPC Codes Based on Distance Graphs
نویسندگان
چکیده
LDPC codes of columnweight of two are constructed fromminimal distance graphs or cages. Distance graphs are used to represent LDPC code matrices such that graph vertices that represent rows and edges are columns. The conversion of a distance graph into matrix form produces an adjacency matrix with column weight of two and girth double that of the graph. The number of 1’s in each row (row weight) is equal to the degree of the corresponding vertex. By constructing graphs with different vertex degrees, we can vary the rate of corresponding LDPC code matrices. Cage graphs are used as examples of distance graphs to design codes with different girths and rates. Performance of obtained codes depends on girth and structure of the corresponding distance graphs.
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عنوان ژورنال:
- EURASIP J. Wireless Comm. and Networking
دوره 2007 شماره
صفحات -
تاریخ انتشار 2007