Fault tolerant decoding method and apparatus including use of quality information

A method of electronic decoding comprising:

• receiving, at a bit quality evaluator, a data stream comprising a sequence of bits;
• assigning, using the bit quality evaluator, a quality measure to each bit within the sequence of bits;
• receiving, at a first decoding device, the sequence of bits and the quality measure;
• performing, using the first decoding device, soft decision convolutional decoding on the sequence of bits using the quality measure;
• identifying, using an off-path detector, an occurrence of a trellis decode path change during the convolutional decoding of the sequence of bits by the first decoder;
• identifying, using the off-path detector, a first symbol proximate to the sequence of bits corresponding to the occurrence of the trellis decode path change;
• identifying, using the erasure decision circuit, at least the first symbol for erasure;
• receiving, at a second decoder, the output of the first decoder and the erasure decision circuit;
• decoding, using a second decoding device, the output of the first decoder after erasing at least the first symbol;
• and
• outputting from the second decoding device decoded corrected data.