The present invention relates to a communication system and in particular but not exclusively to {HEAD ~ a communication system} for use in {TAIL ~ a push} to talk over cellular network 
The present invention relates to a communication system and in particular but not exclusively to { HEAD ~ a communication system } for use in { TAIL ~ a push } to talk over cellular network
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 TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH