Abstract: A method and apparatus for transitioning between control channels in a cellular telecommunications system by using adaptive hysterisis. In an embodiment of the invention, when a mobile station attempts to transition from an analog control channel (ACCH) to a digital control channel (DCCH) and subsequently returns to the ACCH, a threshold level of DCCH received signal strength (rssi) at the mobile station that triggers a transition attempt from an ACCH to a DCCH is incrementally increased. Incrementally increasing the threshold level DCCH rssi prevents unnecessary transitions back and forth between an ACCH and a DCCH when the rssi of the DCCH is close to a minimum level that triggers a camp on the DCCH after a synchronization, or when the mobile station cannot synchronize to or camp on the DCCH successfully.

Abstract: A method is disclosed for operating a mobile station (10), including the steps of, after registering with a first system and camping on a control channel of the first system, (a) leaving the control channel of the first system and sending a registration request to a second system; (b) determining if a registration response is received from the second system; and, if the registration response is not received from the second system, (c) setting a flag. The method further includes the steps of (d) locating a control channel of the first system; (e) testing the state of the flag to determine if it is set; and, if the flag is set, (f) sending a registration request to the first system. In one embodiment of this invention the first system is a digital system, and the second system is an analog system.

Abstract: A method for selecting a digital control channel (DCCH) for a mobile station operating in a cellular system. In the method, after a first DCCH meeting rssi requirements has been located, a search is made for a more preferable second DCCH before camping on the first DCCH. If a more preferred second DCCH is found, the mobile station then camps on the second DCCH. The method includes the process of performing a quick reselection on available digital control channels(DCCH) at points in the selection process, when a first DCCH that meets received signal strength (rssi) criteria at the mobile station has been located using a conventional process, but a more preferable second DCCH could possibly still be found. In an embodiment of the invention the quick reselection may be performed on DCCHs included in a neighbor cell list received on the first DCCH.

Abstract: A mobile station (10) includes a transceiver (14, 16) for receiving information from and for transmitting information to a control channel of a wireless communications system. The mobile station further includes a controller (18) that is bidirectionally coupled to a memory (24) and to the transceiver. The controller executes instructions for implementing a plurality of tasks, including an initialization task, a system access task, an idle task, and a response to an incoming call task. In accordance with the teachings of this invention, the controller is responsive to a receipt of a page message that identifies the mobile station, when executing the initialization task or the system access task, for storing an indication of the receipt of the received page message in the memory.

Abstract: A method for operating a mobile station (10) includes a first step of placing the mobile station in a camping state for receiving a control channel of a communications system. Prior to executing an evaluation of at least one other channels, the method determines if the current communications system was manually selected by a user. If not, the method executes the evaluation of the at least one other channel. If the current communications system was manually selected by the user, the method instead determines if the signal strength of the control channel is equal to or less than a threshold signal strength. If it is, the method executes the evaluation of the at least one other channel; else the method instead returns to the camping state without executing the evaluation of the at least one other channel.