This is achieved by transmitting {HEAD ~ signals} directly over {TAIL ~ the power line} and capturing the reflected signals on that power line 
directly over
This is achieved by transmitting { HEAD ~ signals } directly over { TAIL ~ the power line } and capturing the reflected signals on that power line
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH