A highly efficient time slotted {TAIL ~ version} is disclosed, in which {HEAD ~ transmission} must begin at the start of designated time slots, as well as an unslotted version 
A highly efficient time slotted { TAIL ~ version } is disclosed , in which { HEAD ~ transmission } must begin at the start of designated time slots , as well as an unslotted version
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH