The method 2, wherein the magnitude and {HEAD ~ phase angle} of both the pseudo tracking servo output signal and {TAIL ~ the tracking servo output signal} are identical 
The method 2 , wherein the magnitude and { HEAD ~ phase angle } of both the pseudo tracking servo output signal and { TAIL ~ the tracking servo output signal } are identical
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH