Patent Publication Number: US-2004042442-A1

Title: Methods and apparatus for simultaneous independent voice and data services using a remote subscriber identity module (SIM)

Description:
TECHNICAL FIELD  
       [0001] The present invention relates in general to wireless voice and data communications systems, and in particular, to methods and apparatus for sharing a Subscriber Identity Module (SIM) card between a mobile data station which does not contain the SIM card and a mobile voice station which does contain the SIM card.  
       BACKGROUND  
       [0002] The Global System for Mobile Communications (GSM) General Packet Radio Service (GPRS) is intended to allow the service subscriber the ability to send and receive data in an end-to-end packet transfer mode without utilizing network resources in the circuit-switched mode. GPRS permits efficient use of radio and network resources when data transmission characteristics are i) packet based, ii) intermittent and non-periodic, iii) possibly frequent, with small transfers of data, e.g., less than 500 octets, or iv) possibly infrequent, with large transfers of data, e.g., more than several hundred kilobytes. User applications may include Internet browsers, electronic mail, etc.  
       [0003] The European Telecommunications Standards Institute (ETSI) GSM specifications define for GPRS mobile stations, what is referred to as a “mobile station class,” which specifies some of the behavior to which a mobile station must conform regarding its operation in i) packet mode, ii) circuit-switched mode or iii) both. A Class A mobile station supports simultaneous attachment, monitoring, activation, invocation and traffic flow on both i) circuit-switched voice and ii) packet-switched data services. A Class B mobile station supports simultaneous attachment, monitoring and activation on both i) circuit-switched voice and ii) packet-switched data services, with invocation and traffic flow possible on either service on a mutually exclusive basis. A Class C mobile station supports only non-simultaneous attach, i.e., mutually exclusive attach on either i) circuit-switched voice or ii) packet-switched data services.  
       [0004] The problem among operators and manufacturers stems from the fact that providing a Class A capable mobile station would require both two receivers and transmitters, along with a combiner/duplexer, interface to a common Subscriber Identity Module (SIM) card and possibly an additional call processor, depending upon the number of embedded user-level applications desired to coexist during circuit-switched voice and packet-switched data service operation. This presents the need among mobile station manufacturers to develop a possibly new architecture for such equipment at a higher cost device to the operator. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0005] Features and advantages of the disclosed methods and apparatus will be apparent to those of ordinary skill in the art in view of the detailed description of example embodiments which is made with reference to the drawings, a brief description of which is provided below.  
     [0006]FIG. 1 is a high level block diagram of a communications system illustrating an environment of use for the disclosed system.  
     [0007]FIG. 2 is a more detailed block diagram of the personal computer illustrated in FIG. 1.  
     [0008]FIG. 3 is a more detailed block diagram of the mobile telephone illustrated in FIG. 1.  
     [0009]FIG. 4 is a more detailed block diagram showing the mobile telephone and the personal computer illustrated in FIG. 1.  
     [0010]FIG. 5 is a flowchart of a process for sharing a Subscriber Identity Module (SIM) card between a mobile data station which does not contain the SIM card and a mobile voice station which does contain the SIM card. 
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS  
     [0011] In general, the methods and apparatus described herein facilitate simultaneous independent voice and data services using a remote subscriber identity module (SIM). The methods and apparatus disclosed allow a personal computer (or other data station) which does not contain a SIM card and a mobile phone (or other voice station) which does contain a SIM card to cooperate wirelessly to allow the personal computer to use the SIM card in the mobile phone in a virtual manner. As a result, the personal computer may transmit and receive packet-switched data at the same time the mobile phone is transmitting or receiving a circuit-switched voice signal without interference between the two simultaneous transmissions.  
     [0012] A high level block diagram of an exemplary network communications system  100  is illustrated in FIG. 1. Typically, the system  100  includes one or more mobile telephones  102 , one or more personal computers  104 , one or more circuit-switched voice cells  106 , and one or more packet-switched data cells  108 . Each of the mobile telephones  102  may communicate with each of the circuit-switched voice cells  106  via a wireless connection  110  using a voice communication protocol such as a 2.1 GHz Universal Mobile Telecommunications System (UMTS) protocol. Similarly, each of the personal computers  104  may communicate with each of the packet-switched data cells  108  via another wireless connection  112  using a data communication protocol such as a 900 MHz Global System for Mobile Communication (GSM) protocol. In addition, a mobile telephone  102  and a personal computer  104  located near each other may communicate with each other via yet another wireless connection  114  using another data communication protocol such as a Bluetooth protocol. Using this wireless connection  114  and additional software, as described in detail below, a mobile telephone  102  and a personal computer  104  located near each other may act as a “virtual” Class A GSM device  116  capable of simultaneous voice and data communication.  
     [0013] A more detailed block diagram of a personal computer (PC)  104  is illustrated in FIG. 2. The personal computer  104  may be a laptop computer, a desktop computer, a personal digital assistant (PDA), an Internet appliance, or any other communication device. The personal computer  104  includes a controller  202  which preferably includes a central processing unit (CPU)  204  electrically coupled by an address/data bus  206  to a memory device  208  and one or more interface circuits  210 . The CPU  204  may be any type of well known CPU, such as a microprocessor from the Intel PentiumTM family of microprocessors, the Intel ItaniumTM family of microprocessors, and/or the Intel XScaleTM family of processors. The memory device  208  preferably includes volatile memory and non-volatile memory. Preferably, the memory device  208  stores a software program that interacts with one or more other devices in the system  100  as described below. This program may be executed by the CPU  204  in a well known manner. The memory device  208  may also store digital data indicative of documents, files, programs, web pages, etc. stored during manufacture of the personal computer  104 , retrieved from one or more other devices in the system  100 , and/or loaded via an input device  212 .  
     [0014] The interface circuit(s)  210  may be implemented using any type of well known interface standard, such as an Ethernet interface and/or a Universal Serial Bus (USB) interface. One or more input devices  212  may be connected to the interface circuit  210  for entering data and commands into the controller  202 . For example, the input device  212  may be a keyboard, mouse, touch screen, track pad, track ball, isopoint, and/or a voice recognition system.  
     [0015] One or more displays, printers, speakers, and/or other output devices  214  may also be connected to the controller  202  via the interface circuit  210 . The display  214  may be cathode ray tube (CRTs), liquid crystal displays (LCDs), or any other type of display. The display  214  generates visual displays of data generated during operation of the PC  104 . The display  214  may be used to display web pages, e-mail, etc. The visual displays may include prompts for human operator input, calculated values, detected data, etc.  
     [0016] Preferably, the PC  104  also includes a packet data transceiver  216 . Using the packet data transceiver  216 , the PC  104  may exchange data with one or more packet-switched data cells  108  via a wireless connection  112  to the packet-switched data cells  108 . The wireless connection may be any type of wireless connection, such as a 900 MHz GSM connection. Users of the system  100  may be required to identify themselves to the system as an authorized user. In such an instance, a Subscriber Identity Module (SIM) card containing a valid access code may be required for the activation of services. However, in the preferred embodiment, the SIM card is not present in the PC  104 . The access code may be encrypted prior to transmission across the wireless connection  112 .  
     [0017] In addition, the PC  104  preferably includes a short-range data transceiver  218 , such as a Bluetooth transceiver. Using the short-range data transceiver  218 , the PC  104  may exchange data, such as SIM card data, with a nearby mobile phone  102  via a wireless connection  114  to the mobile phone  102 .  
     [0018] A more detailed block diagram of a mobile phone  102  is illustrated in FIG. 3. The mobile phone  102  may be any type of mobile station. The mobile phone  102  includes a controller  302  which preferably includes a central processing unit (CPU)  304  electrically coupled by an address/data bus  306  to a memory device  308  and one or more interface circuits  310 . The CPU  304  may be any type of well known CPU. The memory device  308  preferably includes volatile memory and non-volatile memory. Preferably, the memory device  308  stores a software program that interacts with one or more other devices in the system  100  as described below. This program may be executed by the CPU  304  in a well known manner. The memory device  308  may also store digital data indicative of documents, files, programs, web pages, etc. stored during manufacture of the mobile phone  102 , retrieved from one or more other devices in the system  100 , and/or loaded via an input device  312 .  
     [0019] The interface circuit(s)  310  may be implemented using any type of well known interface standard. One or more input devices  312  may 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 and/or a voice recognition system.  
     [0020] One or more displays, speakers, and/or other output devices  314  may also be connected to the controller  302  via the interface circuit  310 . The display  314  may be a light emitting diode (LED) display, a liquid crystal display (LCD), or any other type of display. The display  314  generates visual displays of data generated during operation of the mobile phone  102 . The visual displays may include prompts for human operator input, calculated values, detected data, etc.  
     [0021] Preferably, the mobile phone  102  also includes a circuit-switched voice transceiver  316 . Using the voice transceiver  316 , the mobile phone  102  may exchange voice signals with one or more circuit-switched voice cells  106  via a wireless connection  110  to the circuit-switched voice cells  106 . The wireless connection may be any type of wireless connection, such as a 2.1 GHz Universal Mobile Telecommunications System (UMTS) connection. Users of the system  100  may be required to identify themselves to the system as an authorized user. In such an instance, a Subscriber Identity Module (SIM) card containing a valid access code may be required for the activation of services. In the preferred embodiment, the SIM card is present in the mobile phone  102 . The access code may be encrypted prior to transmission across the wireless connection  110 .  
     [0022] In addition, the mobile phone  102  preferably includes a short-range data transceiver  318 , such as a Bluetooth transceiver. Using the short-range data transceiver  318 , the mobile phone  102  may exchange data, such as SIM card data, with a nearby PC  104  via a wireless connection  114  to the PC  104 .  
     [0023] Another detailed block diagram showing the mobile telephone  102  and the personal computer  104  is illustrated in FIG. 4. Both devices include a radio frequency (RF) deck  402 . Each RF deck  402  interfaces an antenna with a digital signal processor (DSP) coder/decoder (codec)  404 . For example, each RF deck  402  typically includes a receiver and a transmitter. The DSP codec  404  samples signals received from the RF deck  402  and decodes the received signals for a call processor  406 . In addition, the DSP codec  404  encodes signals from the call processor  406  for transmission via the RF deck  402 .  
     [0024] Each call processor  406  handles high level control of communications between the mobile station  102 ,  104  and an associated communication cell  106 ,  108 . In order to control communications and other functions for the mobile station  102 ,  104 , each call processor  406  interfaces to a memory management interface (MMI)  408 . In addition, for certain protocols, the call processor  406  must access a Subscriber Identity Module (SIM) card  410 . In the example illustrated in FIG. 4, the mobile phone  102  includes the SIM card  410 . Accordingly, the mobile phone  102  may access the SIM card  410  in a well known manner.  
     [0025] However, the PC  104  may not include a SIM card  410 . Accordingly, the PC  104  access a “virtual” SIM card  412 . In order to access the “virtual” SIM card  412 , the mobile phone may be equipped with a remote SIM server module  414 , and the PC  104  may be equipped with a remote SIM client module  416 . In such an arrangement, when the remote SIM client module  416  requests SIM data, the remote SIM server module  414  supplies the requested data. This process is described in U.S. patent Ser. No. 09/648,955 filed Aug. 5, 2000, which is incorporated herein by reference.  
     [0026] A flowchart of a process  500  for sharing a Subscriber Identity Module (SIM) card  410  between a mobile data station, such as PC  104  which does not contain the SIM card  410 , and a mobile voice station, such as mobile telephone  102  which does contain the SIM card  410  is illustrated in FIG. 5. Preferably, the process  500  is embodied in a software program which is stored in the PC memory  208  and/or the mobile phone memory  308  and executed by the PC CPU  204  and/or the mobile phone CPU  304  in a well known manner. However, some or all of the steps of the process  500  may be performed manually and/or by another device. Although the process  500  is described with reference to the flowchart illustrated in FIG. 5, a person of ordinary skill in the art will readily appreciate that many other methods of performing the acts associated with process  500  may be used. For example, the order of many of the steps may be changed. In addition, many of the steps described are optional.  
     [0027] Generally, the process  500  causes a PC  104  which does not contain a SIM card  410  and a mobile phone  102  which does contain a SIM card  410  to cooperate wirelessly to allow the PC  104  to use the SIM card  410  in the mobile phone  102  in a virtual manner. As a result, the PC  104  may transmit and receive packet-switched data at the same time the mobile phone  102  is transmitting or receiving a circuit-switched voice signal without interference.  
     [0028] The process  500  begins when a PC  104  detects a need for a SIM code from a remote SIM card  410  (block  506 ). For example, a user of the PC  104  may request a web page, send an e-mail message, receive an e-mail message, etc. As a result, the PC  104  may attempt to communicate with a packet-switched data cell  108  via a wireless connection  112  using a data communication protocol which requires a SIM code, such as a GSM protocol. However, if the PC  104  does not contain a SIM card  410 , the PC  104  preferably attempts to use a “virtual” SIM card  412 .  
     [0029] Accordingly, the PC  104  transmits a SIM code request message via a short-range wireless transmitter, such as a Bluetooth transmitter (block  508 ). Subsequently, the mobile phone  102  receives the SIM code request message if the mobile phone  102  is within range of the PC  104  (block  510 ). Preferably, communications between the PC  104  and the mobile phone  102  via the Bluetooth communication channel  114  are private to the PC  104  and the mobile phone  102 .  
     [0030] If the mobile phone  102  is in range and receives the SIM code request message, the mobile phone  102  preferably retrieves the SIM code from a local SIM card  410  in a well known manner (block  512 ). The retrieved SIM code is then transmitted to the PC  104  via the short-range (e.g., Bluetooth) communication channel  114  (block  514 ). As a result, the PC  104  receives the SIM code wirelessly, without the need for a local SIM card  410  (block  516 ).  
     [0031] After the PC  104  receives the SIM code from the remote mobile phone  102 , the PC  104  and the mobile phone  102  may transmit and/or receive signals under the authority of the SIM code simultaneously without radio interference and without requiring the resources of the other. Specifically, the PC  104  may transmit/receive a packet-switched data signal (block  518 ), and the mobile phone  102  may transmit/receive a circuit-switched voice signal (block  520 ). For example, the PC  104  may transmit/receive a 900 MHz GSM packet-switched data signal, and the mobile phone  102  may transmit/receive a 2.1 GHz UMTS circuit-switched voice signal.  
     [0032] In summary, persons of ordinary skill in the art will readily appreciate that methods and apparatus for simultaneous independent voice and data services using a remote subscriber identity module (SIM) have been provided. The foregoing description has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the claimed invention to the exemplary embodiments 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 of examples, but rather by the claims appended hereto.