Abstract:
A method and apparatus for processing embedded messages at a mobile station including a subscriber identity module (SIM) identifying the subscriber, for example, a GSM or a non-GSM wireless telephone. The process includes receiving a message having a protocol identifier, transferring at least a portion of the message to the subscriber identity module if the protocol identifier satisfied a condition, extracting information from the at least portion to of the message at the subscriber identity module if a protocol identified by the protocol identifier is supported by the subscriber identity module.

Description:
TECHNICAL FIELD OF THE INVENTION 
     The present invention relates in general to an apparatus and method for processing wireless telephone call messages and in particular to an apparatus and method for processing an embedded message at a mobile station which includes a subscriber identity module. 
     BACKGROUND OF THE INVENTION 
     In order to offer wireless telephone subscribers increased coverage and functionality, many otherwise incompatible wireless systems are converging. For example, the convergence of TIA/EIA-136 and Global System for Mobile Communication (GSM) technologies is taking place through the use of the GSM GPRS protocol and through network nodes in TIA/EIA-136 networks. Multi-mode mobile stations may be used that are able to function on either a TIA/EIA-136 network or on a GSM network. When either the GSM GPRS protocol stack is used by a TIA/EIA-136 mobile station to obtain packet services, or when a TIA/EIA-136 subscriber (as identified by his subscriber identity module or SIM card) is roaming in a GSM network, it is necessary to deliver native TIA/EIA-136 teleservice messages to the mobile station. 
     Providing such service to the mobile station is problematic because a non-GSM subscriber (e.g., a TIA/EIA-136 subscriber as identified by his SIM card) could be using either a GSM mobile station or a non-GSM mobile station. Further, some of the non-GSM teleservices that are to be delivered to the subscriber may require processing by the mobile station. For example, a non-GSM teleservices may require processing power available in the mobile station, but not available in the SIM card. 
     SUMMARY OF THE INVENTION 
     In one aspect, the invention is directed to a method for processing an embedded message at a mobile station. The mobile station includes a subscriber identity module. The mobile station receives an encapsulating message which includes an embedded message. The mobile station then determines if a protocol identifier included in the encapsulating message is a predetermined protocol identifier. If the protocol identifier is the predetermined protocol identifier, the mobile station transfers the encapsulating message to the subscriber identity module. The subscriber identity module then determines if the particular protocol identified by the protocol identifier is supported by the subscriber identity module. If the particular protocol is supported by the subscriber identity module, the subscriber identity module extracts the embedded message from the encapsulating message and process the embedded message. 
     In another aspect, the invention is directed to a method for processing an embedded message at a mobile station. The mobile station includes a subscriber identity module. The mobile station receives an encapsulating message which includes a protocol identifier, a protocol discriminator, a subscriber identity module escape flag, and the embedded message. The mobile station determines if the protocol discriminator is indicative of a protocol supported by the mobile station. If the protocol discriminator is indicative of a protocol supported by the mobile station, the mobile station determines if the protocol identifier identifies a predetermined protocol. If the protocol identifier identifies the predetermined protocol, the mobile station determines if the subscriber identity module escape flag indicates a desire to transfer the encapsulating message to the subscriber identity module. If the subscriber identity module escape flag does not indicate a desire to transfer the encapsulating message to the subscriber identity module, the mobile station extracts and processes the embedded message. 
     In one embodiment, the mobile station transfers the encapsulating message to the subscriber identity module if the protocol discriminator is indicative of a protocol not supported by the mobile station. The subscriber identity module then determines if the particular protocol identified by the protocol identifier is supported by the subscriber identity module. If the particular protocol is supported by the subscriber identity module, the subscriber identity module extracts and processes the embedded message. In one embodiment, the mobile station transfers the encapsulating message to the subscriber identity module if the subscriber identity module escape flag indicates a desire to transfer the encapsulating message to the subscriber identity module. The subscriber identity module then determines if the particular protocol identified by the protocol identifier is supported by the subscriber identity module. If the particular protocol is supported by the subscriber identity module the subscriber identity module extracts and processes the embedded message. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features and advantages of the present invention will be apparent to those of ordinary skill in the art in view of the detailed description of the preferred embodiment which is made with reference to the drawings, a brief description of which is provided below. 
     FIG. 1 is high level block diagram of a wireless communication system using a GSM base station and a non-GSM mobile station. 
     FIG. 2 is high level block diagram of a wireless communication system using a GSM base station and a GSM mobile station. 
     FIG. 3 is a more detailed block diagram of the mobile station illustrated in FIG.  1  and FIG.  2 . 
     FIG. 4 is a more detailed block diagram of the base station illustrated in FIG.  1  and FIG.  2 . 
     FIG. 5 is a block diagram of the SMS-Deliver message illustrated in FIG.  1  and FIG.  2 . 
     FIG. 6 is a flowchart of a method for processing an embedded message at a mobile station which includes a subscriber identity module. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In general, the system described herein provides a method and apparatus for processing an embedded message at a mobile station. The mobile station may be a Global System for Mobile Communication (GSM) or a non-GSM wireless telephone operating in a wireless communication environment as describe in detail in application Ser. No. 09/407,557 incorporated herein by reference. 
     The mobile station includes a subscriber identity module (i.e., a SIM card). The SIM card is a personalized phone card identifying the subscriber. The SIM card may be inserted in a GSM or a non-GSM wireless telephone. The embedded message is included in an encapsulating message. Some embedded messages are intended for processing by the mobile station. Other embedded messages are intended for processing by the SIM card which is inserted in the mobile station. 
     Preferably, the encapsulating message is a GSM compatible message. However, the embedded message may not be a GSM compatible message. For example, the embedded message may be a TIA/EIA-136 compatible message. Embedded messages intended for processing by the SIM card are passed on to the SIM card by the mobile station. Of course, a person of ordinary skill in the art will readily appreciate that the techniques described herein are equally applicable to systems employing other protocols. 
     A high level block diagram of one such wireless system  100  is illustrated in FIG.  1 . In this example, a GSM base station  102  is transmitting an encapsulating message  104  (e.g., an SMS-deliver message) to a non-GSM mobile station  106  (e.g., a TIA/EIA-136 mobile station). The mobile station  106  contains a non-GSM SIM card  108  (e.g., a TIA/EIA-136 SIM card). 
     A high level block diagram of another wireless system  100  is illustrated in FIG.  2 . In this example, a GSM base station  102  is transmitting an encapsulating message  104  (e.g., an SMS-deliver message) to a GSM mobile station  206 . Even though the mobile station  206  in this example is a GSM mobile station, it contains a non-GSM SIM card  108  (e.g., a TIA/EIA-136 SIM card). 
     A more detailed diagram of the base station  102 , is illustrated in FIG.  3 . In a preferred embodiment, the base station  102  is a GSM cellular base station. However, the base station  102  may be any type of wireless communication system programmed to implement the method and/or apparatus of the present invention. A controller  302  in the base station  102  preferably includes a central processing unit (CPU)  304  electrically coupled by an address/data bus  306  to a memory device  308  and an interface circuit  310 . The CPU  304  may be any type of well known CPU, such as an Intel Pentium™ processor. The memory device  308  preferably includes volatile memory, such as a random-access memory (RAM), and non-volatile memory, such as a read only memory (ROM) and/or a magnetic disk. The memory device  308  stores a software program that implements all or part of the method described below. This program is executed by the CPU  304 , as is well known. However, some of the steps described in the method below may be performed manually or without to the use of the CPU  304 . 
     A receiver  312  and a transmitter  314  are electronically coupled to the controller  302  via a conventional interface circuit  310 . Preferably, the controller  302  receives time-division multiple access (TDMA) signals via the receiver  312 . In response to certain received signals, the controller  302  generates TDMA signals and causes the transmitter  314  to transmit the TDMA signals. Of course, a person of ordinary skill in the art will readily appreciate that other types of signals may be transmitted and/or received in the scope and spirit of the present invention. For example, frequency-division multiple access (FDMA) signals and/or code-division multiple access (CDMA) signals may be used. 
     One or more input devices may also be connected to the interface circuit  310  for entering data and commands into the controller  302 . For example, the input device  312  may be a keyboard, mouse, touch screen, track pad, track ball, isopoint, and/or a voice recognition system. 
     One or more output devices may also be connected to the controller  302  via the interface circuit  310 . Examples of output devices include cathode ray tubes (CRTs), liquid crystal displays (LCDs), speakers, and/or printers. The output device may generate visual displays of data generated during operation of the base station  102 . The visual displays may include prompts for human operator input, run time statistics, calculated values, and/or detected data. 
     A more detailed diagram of the mobile station  106 ,  206 , is illustrated in FIG.  4 . In a preferred embodiment, the mobile station  106 ,  206  is a GPRS-136 cellular handset or a GSM cellular handset. However, the mobile station  106 ,  206  may be any type of wireless communication device programmed to implement the method and/or apparatus of the present invention. At a high level, the mobile station  106 ,  206  is similar to the base station  102  described above. A controller  402  in the mobile station  106 ,  206  preferably includes a central processing unit (CPU)  404  electrically coupled by an address/data bus  406  to a memory device  408  and an interface circuit  410 . The CPU  404  may be any type of well known CPU, such as an Intel Pentium™ processor. The memory device  408  preferably includes volatile memory, such as a random-access memory (RAM), and non-volatile memory, such as a read only memory (ROM) and/or a magnetic disk. The memory device  408  stores a software program that implements all or part of the method described below. This program is executed by the CPU  404 . However, some of the steps described in the method below may be performed manually or without the use of the CPU  404 . 
     A receiver  412  and a transmitter  414  are electronically coupled to the controller  402  via a conventional interface circuit  410 . Preferably, the controller  402  receives time-division multiple access (TDMA) signals via the receiver  412 . In response to certain received signals, the controller  402  generates TDMA signals and causes the transmitter  414  to transmit the TDMA signals. Of course, a person of ordinary skill in the art will readily appreciate that other types of signals may be transmitted and/or received in the scope and spirit of the present invention. For example, frequency-division multiple access (FDMA) signals and/or code-division multiple access (CDMA) signals may be used. 
     One or more input devices may also be connected to the interface circuit  410  for entering data and commands into the controller  402 . For example, the input device  412  may be a keyboard, mouse, touch screen, track pad, track ball, isopoint, and/or a voice recognition system. 
     One or more output devices may also be connected to the controller  402  via the interface circuit  410 . Examples of output devices include cathode ray tubes (CRTs), liquid crystal displays (LCDs), speakers, and/or printers. The output device may generate visual displays of data generated during operation of the mobile station  106 ,  206 . The visual displays may include prompts for human operator input, run time statistics, calculated values, and/or detected data. 
     In addition, the mobile station  106 ,  206  includes a subscriber identification module  108  (SIM card). The SIM card  108  is a personalized phone card identifying the subscriber. The SIM card  108  may be inserted in a GSM or a non-GSM wireless telephone. Preferably, the SIM card  108  includes its own central processing unit  416  (CPU) and memory  418 . Often, the CPU  416  in the SIM card  108  is a different than the CPU  404  in the mobile station  106 ,  206 . The CPU  416  in the SIM card  108  is capable of processing messages received by the receiver  412  completely independent of message processing by the CPU  404  in the mobile station  106 ,  206 . However, in the preferred embodiment, the CPU  404  in the mobile station  106 ,  206  initially receives each message, such as an encapsulating message  104 , from the receiver  412  and then, if necessary, transfers the message to the CPU  416  in the SIM card  108 . Preferably, the memory  418  in the SIM card  108  is non-volatile memory such as FLASH memory. The SIM card  108  may communicate with the mobile station  106 ,  206  via the same interface circuit  410  described above and/or through any other type of well known interface. 
     A more detailed diagram of an encapsulating message  104  is illustrated in FIG.  5 . In the preferred embodiment, the encapsulating message  104  is an SMS-deliver message  104 . The SMS-deliver message  104  includes a protocol identifier field  502  (e.g., TP-PID). The protocol identifier field  502  may indicate that the SMS-deliver message  104  is using a user data portion  504  to deliver a non-GSM teleservice message using a tunneling of teleservice message protocol (i.e., TOTEM). 
     The user data portion  504  preferably includes a protocol discriminator  506 . The protocol discriminator  506  is different than the protocol identifier  502 . The protocol discriminator  506  indicates which non-GSM protocol is being used in the embedded message (e.g., TIA/EIA-136). The user data portion  504  may also include a SIM escape flag  508  and/or other data which may be used to indicate whether the mobile station  106 ,  206  should process the teleservice message or if the mobile station  106 ,  206  should pass the message on to the SIM card  108  for processing. However, the mobile station  106 ,  206  may pass the message on to the SIM card  108  for processing even when the SIM escape flag  508  is not set, as described in detail below. Although, for simplicity in explanation, a SIM escape flag  508  is used throughout this description, a person of ordinary skill in the art will readily appreciate that any field or combination of fields may be processed to determine if the mobile station  106 ,  206  should pass the message on to the SIM card  108  for processing. Finally, the user data portion  504  also includes the embedded message  510 . For example, the user data portion  504  may include a TIA/EIA-136 embedded message  510 . Of course, the encapsulating message  104  and/or the user data portion  504  may also include other data  512   
     A flowchart of a method  600  for processing an embedded message  510  at a mobile station  106 ,  206  which includes a subscriber identity module  108  is illustrated in FIG.  6 . Generally, an embedded message  510  is included in an encapsulating message  104  and transmitted to the mobile station  106 ,  206  by the base station  102 . Some embedded messages  510  are intended for processing by the mobile station  106 ,  206 . Other embedded messages  510  are intended for processing by the SIM card  108  which is inserted in the mobile station  106 ,  206 . Preferably, the encapsulating message  104  is a GSM compatible message. However, the embedded message  510  may not be a GSM compatible message. For example, the embedded message  510  may be a TIA/EIA-136 compatible message. Embedded messages  510  intended for processing-by the SIM card  108  are passed on to the SIM card  108  by the mobile station  106 ,  206 . 
     The method  600  begins when an SMS-deliver message  104  is received by the mobile station  106 ,  206  (step  602 ). If the mobile station  106 ,  206  is a GSM mobile station  206 , it checks the protocol identifier field  502  for an indication that the SMS-deliver message  104  is using the user data portion  504  to deliver a non-GSM teleservice message using a tunneling of teleservice message protocol (e.g., TP-PID=TOTEM) (step  606 ). If the protocol identifier field  502  does indicate that the SMS-deliver message  104  is using the user data portion  504  to deliver a non-GSM teleservice message using a tunneling of teleservice message protocol, the GSM mobile station  206  passes the entire SMS-deliver message  104  to the SIM card  108  for processing (step  608 ). 
     The SIM card  108  then checks the protocol identifier field  502  to determine if it supports the identified protocol (e.g., TOTEM) (Step  610 ). If the SIM card  108  determines that it does support the protocol identified by the protocol identifier field  502 , the SIM card  108  extracts the embedded message (e.g., a TIA/EIA-136 message) and processes the embedded message using the SIM card CPU  416  (step  612 ). If the protocol identifier field  502  does not indicate that the SMS-deliver message  104  is using the user data portion  504  to deliver a non-GSM teleservice message using a tunneling of teleservice message protocol (step  606 ), or the SIM card  108  determines that it does not support the protocol identified by the protocol identifier field  502 , the method  600  ends without processing the embedded message  510 . 
     If the mobile station  106 ,  206  is a non-GSM mobile station  106 , it checks if it supports the non-GSM protocol being used by the embedded message (e.g., TIA/EIA-136) as indicated in the protocol discriminator  506  (step  614 ). If the non-GSM mobile station  106  supports the non-GSM protocol being used by the embedded message, the non-GSM mobile station  106  checks the protocol identifier field  502  for an indication that the SMS-deliver message  104  is using the user data portion  504  to deliver a non-GSM teleservice message using a tunneling of teleservice message protocol (e.g., TP-PID=TOTEM) (step  616 ). If the protocol identifier field  502  does not indicate that the SMS-deliver message  104  is using the user data portion  504  to deliver a non-GSM teleservice message using a tunneling of teleservice message protocol, the method  600  ends without processing the embedded message  510 . If the protocol identifier field  502  does indicate that the SMS-deliver message  104  is using the user data portion  504  to deliver a non-GSM teleservice message using a tunneling of teleservice message protocol, the GSM mobile station  206 .checks the SIM escape flag  508  and/or other data (step  618 ). 
     If the SIM escape flag  508  is set or other data in the message is indicative of a SIM escape function, the non-GSM mobile station  106  passes the entire SMS-deliver message  104  to the SIM card  108  for processing (step  608 ). As described above, the SIM card  108  then checks the protocol identifier field  502  to determine if it supports the identified protocol (e.g., TOTEM) (Step  610 ). If the SIM card  108  determines that it does support the protocol identified by the protocol identifier field  502 , the SIM card  108  extracts the embedded message (e.g., a TIA/EIA-136 message) and processes the embedded message using the SIM card CPU  416  (step  612 ). If the SIM escape flag  508  is not set (step  618 ), the non-GSM mobile station  106  extracts the embedded message (e.g., a TIA/EIA-136 message) and processes the embedded message using the mobile station  106  CPU  404  (step  620 ). 
     In summary, persons of ordinary skill in the art will readily appreciate that a method and apparatus for processing an embedded message at a mobile station which includes a subscriber identity module has been provided. Systems implementing the teachings of the present invention can enjoy the flexibility of inserting non-GSM SIM cards into GSM mobile stations while maintaining the compatibility and the ability to efficiently process teleservice messages. 
     The foregoing description has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of the above teachings. It is intended that the scope of the invention be limited not by this detailed description, but rather by the claims appended hereto.