A message update function specifically defined as part of the invention, is used to determine the outgoing message at the variable node, and {HEAD ~ the simple min operation} along with {TAIL ~ modulo 2 sum} of signs is used at the check node 
A message update function specifically defined as part of the invention , is used to determine the outgoing message at the variable node , and { HEAD ~ the simple min operation } along with { TAIL ~ modulo 2 sum } of signs is used at the check node
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH