Abstract: A method is employed by a central controller of a radio communications system, which method provides for sustaining a predetermined level of communication service. The system includes a plurality of voice channels which are allocated among a plurality of subscribers (108-112) using a first control channel (102). In a preferred embodiment, at least one of the voice channels (104, 106) is also control-capable. The method includes evaluating (502) a current loading condition, and comparing (504) this loading condition with an upper loading threshold. Where appropriate, the controller assigns (506) one of the control-capable voice channels as a temporary control channel.

Abstract: A method (215) of converting a current control channel for use as a communication (voice/data) channel, in order to maintain a predetermined level of service in a radio communications system, employs a central controller (101) to allocate a limited number of communication channels among a plurality of subscriber units (108-112). After receiving (203) a request for a communication channel from one of a plurality of subscriber units (108-112), the controller (101) determines (205) whether all of the communication channels are busy. The controller then temporarily converts (215) the current control channel to a communication channel.