A second pair of signals is derived from the first pair of signals in which {HEAD ~ the second pair} are displaced in {TAIL ~ phase} relative to the first pair and are also in phase quadrature 
are displaced in
A second pair of signals is derived from the first pair of signals in which { HEAD ~ the second pair } are displaced in { TAIL ~ phase } relative to the first pair and are also in phase quadrature
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH