Improved Hard Iterative Decoding (IHID) of Multilevel Codes

An improved hard iterative decoding (IHID) algorithm is presented to efficiently terminate hard iterations in the decoding of multi-level codes. The proposed terminating policy stops iterations as soon as a valid path on the super trellis is found thereby only running the minimum required number of iterations. The IHID decoding algorithm performs better than the conventional multi-stage decoding by reducing the effects of error multiplicity. Compared with known hard iterative decoding with fixed number of iterations, the IHID algorithm can significantly reduce decoding complexity and decoding delay.