Date Added: Dec 2012
The demand for flexible broadband wireless services makes the pruning technique, including both shortening and puncturing, an indispensable component of error correcting codes. The analysis of the pruning process for structured Low-Density Parity-Check (LDPC) codes can be considerably simplified with their equivalent representations through base-matrices or protographs. In this paper, the authors evaluate the thresholds of the pruned base-matrices by using Protograph based on EXtrinsic Information Transfer (PEXIT). They also provide an efficient method to optimize the pruning patterns, which can significantly improve the thresholds of both the full-length patterns and the sub-patterns.