METHOD AND APPARATUS FOR ERROR CORRECTION DECODING A NORDSTROM-ROBINSON ENCODED DATA STREAM

摘要

A method and apparatus are provided for decoding areceived data block encoded with a Nordstrom-Robinsoncodeword. The method and apparatus reduce the number ofmathematical operations necessary to decode the datablock. The method and apparatus divide the received datablock 600 into subsets 601-604 and calculate a maximumconfidence quadracodeword (QCW) character for each datasubset 601-604 to form a set of maximum confidence QCWcharacters (step 304). A set of maximum confidencequadracodewords 802-809 is determined based on the set ofmaximum confidence QCW characters (step 306). At leastone NR codeword 1102 is identified that corresponds toeach maximum confidence quadracodeword 802-809 in the setof maximum confidence quadracodewords to thereby form aset of NR codewords (step 308). A single NR codeword isthen selected from the set of NR codewords and then usedto decode the received data block.