The Performance of LDPC codes with Large Girth
نویسندگان
چکیده
We experiment with variations of a method for constructing low-density paritycheck codes to investigate the effect on decoding performance under the sumproduct algorithm. The method uses circulant permutation matrices or affine permutation matrices as building blocks. We have developed an algorithm to choose these matrices so as to maximize the girth of the parity-check matrix. Substantial performance gains result from requiring large girth, but other factors also play a role. Simulations were conducted using a wide-area computational grid program, which allowed investigation of high signal-to-noise ratios and their corresponding low output bit error rates.
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