Within the IS 54 standard, which describes the interface between mobile and base equipment for North American digital cellular systems, each information time slot is preceded by {HEAD ~ a known sequence}, designated as {TAIL ~ the preamble} 
designated as
Within the IS 54 standard , which describes the interface between mobile and base equipment for North American digital cellular systems , each information time slot is preceded by { HEAD ~ a known sequence } , designated as { TAIL ~ the preamble }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL