{HEAD ~ The non linear section} is coupled in {TAIL ~ a feedback manner} with the quantized linear section 
is coupled in
{ HEAD ~ The non linear section } is coupled in { TAIL ~ a feedback manner } with the quantized linear section
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH