The modem provides {HEAD ~ a calibration signal} for calibrating {TAIL ~ a modulation characteristic} of the supply modulator, to the supply modulator 
The modem provides { HEAD ~ a calibration signal } for calibrating { TAIL ~ a modulation characteristic } of the supply modulator , to the supply modulator
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH