{HEAD ~ A pseudo tracking servo output signal} is generated according to {TAIL ~ the simulation parameters} of the tracking servo output signal 
is generated according to
{ HEAD ~ A pseudo tracking servo output signal } is generated according to { TAIL ~ the simulation parameters } of the tracking servo output signal
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH