The method 6 wherein the predetermined characteristic is {HEAD ~ a predetermined range} of {TAIL ~ power levels} for the fiber optic signal 
The method 6 wherein the predetermined characteristic is { HEAD ~ a predetermined range } of { TAIL ~ power levels } for the fiber optic signal
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH