Method and system for using SIM card in CDMA service area

A method for allowing a GSM subscriber to use a SIM card in a CDMA service area using a CDMA terminal, the CDMA terminal including a detachable SIM card and a SIM interface for interfacing between the SIM card and the CDMA terminal, the method comprising the steps of:

• a) sending a verification confirm request for the SIM card to a CDMA subsystem using unique subscriber information stored in the SIM card mounted in the CDMA terminal;
• b) upon receipt of the unique subscriber information for SIM card verification, sending, at the CDMA subsystem, a verification confirm request to a GSM subsystem using the unique subscriber information and information about a predetermined agreement with the GSM system;
• c) sending a verification result for the SIM card from the GSM subsystem to the CDMA subsystem via a public network in response to the verification confirm request;
• a
• d) upon receipt of the verification result for the SIM card from the GSM subsystem, assigning, at the CDMA subsystem, a unique virtual management number for the CDMA terminal mounted with the SIM card and sending SIM card verification result to the CDMA terminal so as to enable the CDMA terminal to use the SIM cards
• e) calculating, at the CDMA subsystem, a call charge based on information required for call charge upon completion of a call;
• and
• f) sending the calculated call charge to a GSM system via the public network.

A method for allowing a subscriber of a CDMA terminal mounted with a SIM card to make a phone call to another subscriber in a system which allows the subscriber to use the SIM card in a CDMA service area using a CDMA terminal, the CDMA terminal including a detachable SIM card and a SIM interface for interfacing between the SIM card and the CDMA terminal, the method comprising the steps of:

• determining, at a CDMA subsystem, whether the other subscriber is a subscriber of the same CDMA subsystem in response to a call request from the CDMA terminal mounted with the SIM card;
• setting up a call to the other subscriber using a corresponding network, when the other subscriber is a subscriber of the same CDMA subsystem;
• calculating, at the CDMA subsystem, a call charge based on information required for call charge upon completion of the call;
• and
• sending the calculated call charge to a GSM system via the public network.

A method for allowing another subscriber of a CDMA network to make a phone call to a subscriber of a CDMA terminal mounted with a SIM card in a system which allows the subscriber to use the SIM card in a CDMA service area using a CDMA terminal, the CDMA terminal including a detachable SIM card and a SIM interface for interfacing between the SIM card and the CDMA terminal, the method comprising the steps of:

• allowing the other subscriber of the CDMA network to send a call request by inputting a country code and a GSM phone number for a user of the SIM card;
• determining, at a CDMA subsystem, whether a unique management number for the country code and the GSM number has been updated, in response to a call request;
• and
• setting up a call between the other subscriber of the CDMA network and the CDMA terminal mounted with the SIM card when the unique management number has been updated.

A method for allowing a wire subscriber in a CDMA service area to make a phone call to a subscriber of a CDMA terminal mounted with a SIM card in a system which allows the subscriber to use the SIM card in a CDMA service area using a CDMA terminal, the CDMA terminal including a detachable SIM card and a SIM interface for interfacing between the SIM card and the CDMA terminal, the method comprising the steps of:

• allowing the wire subscriber to send a call request by inputting a country code and a GSM phone number for a user of the SIM card;
• determining, at a wire network and a CDMA subsystem, whether a unique management number for the country code and the GSM number has been updated, in response to a call request;
• and
• setting up a call between the wire subscriber in the CDMA service area and the CDMA terminal mounted with the SIM card when the unique management number has been updated.

A method for allowing a GSM subscriber in a CDMA service area to make a phone call to a subscriber of a CDMA terminal mounted with a SIM card in a system which allows the subscriber to use the SIM card in a CDMA service area using a CDMA terminal, the CDMA terminal including a detachable SIM card and a SIM interface for interfacing between the SIM card and the CDMA terminal, the method comprising the steps of:

• allowing the GSM subscriber to send a call request by inputting a GSM phone number for a user of the SIM card;
• determining whether a subscriber for the GSM phone number is in the CDMA service area, in response to the call request;
• notifying the GSM subscriber that a present call is an international call, when the subscriber for the GSM phone number is in the CDMA service area;
• and
• setting up a call between the GSM subscriber and the CDMA terminal mounted with the SIM card via a public network, when the GSM subscriber accepts the international call.

A method for allowing a wire subscriber in a GSM service area to make a phone call to a subscriber of a CDMA terminal mounted with a SIM card in a system which allows the subscriber to use the SIM card in a CDMA service area using a CDMA terminal, the CDMA terminal including a detachable SIM card and a SIM interface for interfacing between the SIM card and the CDMA terminal, the method comprising the steps of:

• allowing the wire subscriber to send a call request by inputting a GSM phone number for a user of the SIM card;
• determining, at a wire network and a CDMA subsystem, whether a subscriber for the GSM phone number is in the CDMA service area, in response to a call request;
• and
• notifying the wire subscriber that a present call is an international call, when the subscriber for the GSM phone number is in the CDMA service area;
• and
• setting up a call between the wire subscriber in the GSM service area and the CDMA terminal mounted with the SIM card via a public network, when the wire subscriber accepts the international call.

A method for registering and searching a phone number for an additional service in a system which allows a subscriber to use the SIM card in a CDMA service area using a CDMA terminal, the CDMA terminal including a detachable SIM card and a SIM interface for interfacing between the SIM card and the CDMA terminal, the method comprising the steps of:

• outputting a message requesting a user of the CDMA terminal to choose a device where to register a phone number, as the user inputs a phone number registration function key and a phone number to be registered;
• registering the phone number in the SIM card or an internal memory according to the user's choice;
• searching a list of phone numbers stored in the internal memory and the SIM card upon receipt of a phone book search function key and search information;
• and
• upon detection of a phone number corresponding to the search information, providing the phone number to the user.

A system for allowing a GSM (Global System for Mobile communication) subscriber to use a SIM (Subscriber Identity Module) card in a CDMA (Code Division Multiple Access) service area, the system comprising:

• a CDMA terminal in which the SIM card can be mounted, said CDMA terminal reading unique subscriber information for SIM card verification from the SIM card and sending the read unique subscriber information, and enabling the SIM card upon receipt of verification for the SIM card;
• a CDMA subsystem for sending a verification confirm request for the SIM card to a GSM subsystem using the unique subscriber information and information about a predetermined agreement with a GSM system upon receipt of the unique subscriber information for SIM card verification;
• assigning a unique virtual management number for the CDMA terminal mounted with the SIM card and sending SIM card verification to the CDMA terminal when the GSM subsystem verifies the SIM card;
• calculating a call charge based on information required for call charge upon completion of a call;
• and sending the calculated call charge to the GSM system;
• the GSM subsystem verifying the SIM card in response to the verification confirm request for the SIM card and sending the verification result to the CDMA subsystem;
• and
• a public network for connecting the CDMA subsystem and the GSM subsystem.