In {TAIL ~ the control unit} {HEAD ~ a phase measurement} is carried out and an evaluation device computes the distance information from the phase difference 
In
In { TAIL ~ the control unit } { HEAD ~ a phase measurement } is carried out and an evaluation device computes the distance information from the phase difference
REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH