Abstract: In a communication system network, a communication unit may maintain allocation of a telephone resource when it roams into another communication system. Having established a communication in a first communication system, the communication unit is allocated a communication resource in the first communication system and is also allocated a telephone resource. While the communication unit is allocated the communication resource and the telephone resource, it determines whether the transceiving quality of the allocated communication resource has degraded below a predetermined level. When the transceiving quality has degraded below a predetermined level, the communication unit transmits a registration packet to second communication system via the central controller. Upon receiving the registration packet, the central controller reclaims the allocated communication resource in the first communication unit and attempts to allocate a communication resource in the second communication system.

Abstract: In a communication system network, the central controller may more efficient respond to group regrouping requests in the following manner. Once a console generates a dynamic group regrouping request which requests the regrouping of a set of communication groups into a super group, the central controller determines, for each communication system, whether at least one of the set of communication groups is registered in that communication system. When at least one of the set of communication groups is registered in the communication system, the central controller groups the at least one of the set of communication groups into a local super communication group. Having done this, the central controller then generates super communication group information and transmits it to the communication systems but only that portion that pertains to the local super communication group.

Abstract: In a trunked communication system with at least two communication sites, a call hand-off mid-call may occur when a mobile radio (109) moves from the coverage area of one site to the coverage area of another site. This second site may not have any communication resources available for this hand-off, and the radio (109) is issued a busy message. With user selectable site switching, the user may enter into the radio (221) the desire to return to the previous site, and the radio moves to the previous channel to continue (229) receiving the call.

Abstract: An enhanced talkgroup scanning algorithm is provided. This algorithm provides an efficient scan function when a unit scan list contains a mixture of trunked talkgroups and conventional channels. This is accomplished by adding a new scanning algorithm for conventional priority groups, and by enhancing the trunking talk group scanning cycle. A novel scanning algorithm for conventional priority groups is used to decrease the audio holes in trunking calls when looking back at a priority conventional channel. When a unit is active on a low priority trunking call and goes over to the priority conventional channel to check for activity, several new steps are taken into consideration when the unit goes back to the trunked system/active trunked call. Based on whether there has been activity on the priority channel, the unit will immediately return to the old voice channel (unsquelched) or revert to the control channel.

Abstract: A radio communication controller (106, 401) is disclosed which is capable of accessing a database having a subscriber unit identification code (302, 601) and a preselected calling code, or area code, accumulating a keyed Public Switched Telephone Network (PSTN) telephone number from the subscriber unit wishing to make an interconnect call (110, 407), and comparing (215, 518) this area code with that of the controller site. The controller, as employed by the invention, is further capable of deciding whether or not the area code is required for completing the interconnect call, and if so, prefacing (217, 520) the accumulated PSTN telephone number with the area code preselected by the user of that subscriber unit.

Abstract: A typical multi-site trunked communication system comprises communication units that are arranged into talk groups, communication resources distributed among communication sites, and a communication resource allocator. In such a system, a methodology is incorporated that allows communication units to override communication site busy conditions, where the communication site busy conditions prohibits placement of group calls until all communication sites have an available communication resource. The communication site busy condition may be overridden by a communication unit by initiating a busy override signal. Once the busy override signal is initiated, the communication resource allocator allocates, in each site, a communication resource to the communication group of the requesting communication unit.