Abstract: A radiotelephone system having DCCH channels includes an over-the-air activation teleservice sub-system (OTAF) for programming mobile stations (MS) with Intelligent Roaming (IR) information. Each MS includes a history list containing the most recently used DCCHs. The IR information sent to a MS includes data for setting the number of entries in the history list, data for setting the content of the history list entries, and a data for setting the power level threshold. The number of entries in each MS can be optimally set according to the number of DCCHs in a network with networks having a greater number of DCCHs being able to place a greater number of entries in the history list of their subscribing MSs. The content of the history list, moreover, may be optimally set for a network and for a particular cell or group of cells in a network. Thus, for instance, an MS entering a new network can be programmed to have the DCCHs of the new network. The power level threshold is used by the MS to detect suitable DCCHs.

Abstract: A method for authenticating a cellular service provider during over the air activation of a mobile station includes the steps of programming an A-key value into the mobile station and providing the A-key value to the service provider. The mobile station requests over the air activation by transmitting a registration request to the service provider. The service provider verifies billing information and generates two random numbers. The service provider then performs a first CAVE algorithm using the provided A-key value and the first random number to generate a first shared secret data value. The service provider performs a second CAVE algorithm using the first shared secret data value and the second random number to produce a first authentication value. The service provider then transmits the first and second random numbers along with the authentication value to the mobile station.

Abstract: A method and an apparatus for selecting a cellular carrier frequency for accessing cellular airtime services based upon a list of preferred system identification codes (SIDs). A cellular telephone is programmed to accept into memory a list of preferred SIDs corresponding to carriers through which service is preferred. While any SID remains in a preferred list, the standard A/B system selection function is replaced by a substitute system selection function which includes only three carrier selection modes including the Home Only mode, the SID Only mode, and a Roam Saver mode. With the Roam Saver carrier selection mode, the cellular telephone first prefers service through a home carrier and then through a carrier broadcasting a SID matching a SID on the preferred list, but never denies service to emergency or non-emergency destinations if any SID is detected.

Abstract: A method and an apparatus for selecting a cellular carrier frequency for accessing cellular airtime services based upon a list of preferred system identification codes (SIDs). A cellular telephone is programmed to accept into memory a list of preferred SIDs corresponding to carriers through which service is preferred. While any SID remains in a preferred list, the standard A/B system selection function is replaced by a substitute system selection function which includes only three carrier selection modes including the Home Only mode, the SID Only mode, and a Roam Saver mode. With the Roam Saver carrier selection mode, the cellular telephone first prefers service through a home carrier and then through a carrier broadcasting a SID matching a SID on the preferred list, but never denies service to emergency or non-emergency destinations if any SID is detected.

Abstract: A method and an apparatus for selecting a cellular carrier frequency for accessing cellular airtime services based upon a list of preferred system identification codes (SIDs). A cellular telephone is programmed to accept into memory a list of preferred SIDs corresponding to carriers through which service is preferred. While any SID remains in a preferred list, the standard A/B system selection function is replaced by a substitute system selection function which includes only three carrier selection modes including the Home Only mode, the SID Only mode, and a Roam Saver mode. With the Roam Saver carrier selection mode, the cellular telephone first prefers service through a home carrier and then through a carrier broadcasting a SID matching a SID on the preferred list, but never denies service to emergency or non-emergency destinations if any SID is detected.

Abstract: A remotely programmable radiotelephone and a remote programming unit. The radiotelephone (10) includes a receiver front end and demodulator (23), receiver signal processing circuits (30), a dual-tone, multiple-frequency converter (31), a controller (50), and a memory (51). The converter (31) converts DTMF tones into digital signals. The controller (50) monitors the output of the converter (31). If the output corresponds to a valid command then the controller (50) executes the command. Certain commands must be preceded by the user entering an access code using a control keypad (56) and by the reception of DTMF tones corresponding to a password or security code stored in the memory (51). Some commands cause telephone numbers to be stored in the memory (51) for later recall by the user. Other commands cause a number to be stored and an outgoing call to be automatically initiated.