US Patent 7953396 Reducing latency in push to talk services

A method of processing user speech data for transmission to a participant or participants in a Push to talk Over Cellular (PoC) session over a cellular telephone network. The method comprises, detecting an initial period of silence in the initial talk burst of the session, and removing that period of silence from the speech data prior to replaying of the speech data to the or each other participant. These signal processing steps may be carried out at one of the initiating terminal, the receiving terminal, or the IMS core.