Patent ID: 7729303
Filing Date: 2010-06-01
Classification: H04B,H04W

Abstract:
1. A CDMA communication system, comprising: a plurality of base transceiver stations spatially distributed to communicate with mobile communication devices via radio links; a plurality of base station controllers, each coupled to a plurality of base transceiver stations; a mobile switching center connected to couple said base station controllers to a public telephone network; a data communication system comprising (1) a plurality of packet control function devices respectively connected to said base station controllers to transmit data packets to and from the mobile communication devices via said base transceiver stations, and (2) a packet data serving node connected to said packet control function devices to provide packet data services to the mobile communication devices; and a trunking system comprising (1) a plurality of dispatching clients respectively connected to said base station controllers to transmit data packets of group calls to and from mobile communication devices of groups of subscribers where members of each group share a common trunking data link for transmission of data packets, and (2) at least a first dispatching server connected to communicate with a first group of said dispatching clients that are located in a first geographic region and at least a second dispatching server connected to communicate with a second group of said dispatching clients that are located in a second geographic region, wherein each dispatching server and corresponding dispatching clients are operable in combination to provide a push-to-talk function for a group call within each group, and wherein each dispatching server comprises at least one control node to control and manage group call processing and at least one serving node to process voice data for group calls from mobile communication devices registered in the each dispatching server, and wherein each dispatching server directs a group call from a roaming mobile communication device registered to another dispatching server to the other dispatching server for processing.