System and method for providing error correction coding with selectively variable redundancy

摘要

A system and method are disclosed for providing error correction coding having a selectively variable degree of redundancy. The system and method include generating extended check symbols by performing a Reed-Solomon operation on unused check symbols that do not form a portion of an interleaved code word. An extended check symbol is generated from the unused check symbols appearing in a column of the unused check symbols. The extended check symbols are stored with the interleaved code words in a data storage device. The extended check symbols are retrieved from the data storage device with the corresponding interleaved code words. Following the decoding of the interleaved code words and the identification of uncorrectable errors therein, the extended check symbols are decoded to recover the corresponding unused check symbols for the previously uncorrectable interleaved code words. The recovered unused check symbols are added to the previously uncorrectable interleaved code words so as to increase the error correcting capability thereof. The previously uncorrectable interleaved code words having the recovered unused check symbols are then decoded and errors therein corrected accordingly.