Thus, any occurrence of {TAIL ~ a combination} of sequences that causes {HEAD ~ large interference} may reduce the communications quality 
Thus , any occurrence of { TAIL ~ a combination } of sequences that causes { HEAD ~ large interference } may reduce the communications quality
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH