{TAIL ~ The message} passing {HEAD ~ decoder} 8, wherein the LDPC codes have a fixed column weight 
{ TAIL ~ The message } passing { HEAD ~ decoder } 8 , wherein the LDPC codes have a fixed column weight
TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH