Abstract: Disclosed is a CDMA terminal for providing a CDMA service to a global system for mobile communications (GSM) service subscriber in a CDMA service area which comprises: a subscriber identity module (SIM) cardholder for installing or uninstalling a SIM card of a GSM service subscriber, wherein when a SIM card of the GSM service subscriber is installed in the SIM cardholder in the CDMA service area, specific data are transmitted using a CDMA message in the case of authenticating the GSM service subscriber using information on the GSM service subscriber stored in the SIM card, and when the authentication of the GSM service subscriber is normally completed, the CDMA terminal is used for the GSM service subscriber as a roaming service terminal in the CDMA service area. According to the present invention, the GSM service subscriber can use his SIM card and number in the CDMA service area.

Abstract: Disclosed is a roaming service system in a CDMA service area for GSM service subscribers, which comprises a CDMA system comprising a CDMA HLR storing information on subscribers' locations and services, a CDMA MSC connected to the CDMA HLR and accessing calls, and a CDMA terminal wirelessly connected to the CDMA MSC and capable of having a SIM card removably installed therein; a GSM system comprising a GSM HLR storing information on the subscribers' locations and services, a GSM MSC connected to the GSM HLR and accessing calls, an authentication center (AuC) connected to a GSM network and authenticating terminals, and a GSM terminal wirelessly connected to the GSM MSC; and an IRGS connected between the CDMA system and the GSM system and converting signals to execute signal communications between the systems, and when a subscriber of a service provided by the GSM system moves to an area in which the subscriber can use the service provided by the CDMA system and installs the subscriber's SIM card

Abstract: Disclosed is a CDMA terminal for providing a CDMA service to a global system for mobile communications (GSM) service subscriber in a CDMA service area which comprises: a subscriber identity module (SIM) cardholder for installing or uninstalling a SIM card of a GSM service subscriber, wherein when a SIM card of the GSM service subscriber is installed in the SIM cardholder in the CDMA service area, specific data are transmitted using a CDMA message in the case of authenticating the GSM service subscriber using information on the GSM service subscriber stored in the SIM card, and when the authentication of the GSM service subscriber is normally completed, the CDMA terminal is used for the GSM service subscriber as a roaming service terminal in the CDMA service area. According to the present invention, the GSM service subscriber can use his SIM card and number in the CDMA service area.

Abstract: Disclosed is a roaming service system in a CDMA service area for GSM service subscribers, which comprises a CDMA system comprising a CDMA HLR storing information on subscribers' locations and services, a CDMA MSC connected to the CDMA HLR and accessing calls, and a CDMA terminal wirelessly connected to the CDMA MSC and capable of having a SIM card removably installed therein; a GSM system comprising a GSM HLR storing information on the subscribers' locations and services, a GSM MSC connected to the GSM HLR and accessing calls, an authentication center (AuC) connected to a GSM network and authenticating terminals, and a GSM terminal wirelessly connected to the GSM MSC; and an IRGS connected between the CDMA system and the GSM system and converting signals to execute signal communications between the systems, and when a subscriber of a service provided by the GSM system moves to an area in which the subscriber can use the service provided by the CDMA system and installs the subscriber's SIM card in the CDMA ter