In mobile radio receivers, the transmission power must be raised before the start of {HEAD ~ the transmission process}, and must be reduced again after {TAIL ~ the end} of the transmission process 
In mobile radio receivers , the transmission power must be raised before the start of { HEAD ~ the transmission process } , and must be reduced again after { TAIL ~ the end } of the transmission process
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH