Patent ID: 7702348

Claim:
A method of fast call setup in digital trunking communication system, comprising the steps of: 1) initiating, by a terminal, a request for a push-to-talk (PTT) call; 2) receiving, by a base station, the request for the PTT call; assigning by the base station a channel resource for the PTT call, in order to establish by the base station a forward service channel in accord with a distribution of channels, transmitting at a same time by the base station: one or more empty frames on the forward service channel; and an extended channel assignment message to specify a service channel assigned for the terminal; 3) receiving by the terminal the extended channel assignment message, then at the same time: opening by the terminal a receiver to track and acquire the forward service channel; and transmitting by the terminal one or more prefix-frames; and 4) attempting by the base station and the terminal to acquire service channels simultaneously, so as to complete the call setup, wherein if the attempting to acquire the service channels fails, the channel resource for the PTT call is released.