Patent ID: 8159996

Claim:
A control method for re-access after a terminal in a trunking system exits a group call, including the following steps of: (a) a dispatching system maintaining one message number for every group call, updating message numbers for various calls in one group, and sending this message number to the terminal when a call is established; (b) the terminal accessing to a group call, receiving and retaining the message number of the group, setting an exit symbol as “unable to passively access” type when the terminal exits the group call normally, and setting the exit symbol as “able to passively access” type when the terminal exits the group call abnormally or the group call is released; (c) the terminal in idle state receiving a paging message of said group periodically transmitted by a base station, judging whether the exit symbol of the corresponding group is “able to passively access” type, if yes, step (e) being performed; if the exit symbol is “unable to passively access” type, step (d) being performed; (d) the terminal determining whether the message number retained for the group is the same as the message number in the paging message, if yes, discarding the paging message; otherwise, step (e) being performed; and (e) the terminal receiving and processing the paging message, accessing the call, and retaining the message number if it is new.