Abstract:
A mobile device includes first identification circuitry and second identification circuitry. The first identification circuitry is associated with a first network and the second identification circuitry is associated with a second network. The mobile device simultaneously registers itself with the first and second networks using the first and second identification circuitry, respectively. The first and second identification circuitry may each comprise subscriber identity modules. The mobile devices handle outgoing and incoming calls based on user preferences. The user may override the preferences for selected calls.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Technical Field 
         [0002]    The present invention relates generally to the field of mobile devices, and more particularly to a mobile telephone having more than one simultaneously active subscriber identity modules (SIMs). 
         [0003]    2. Description of the Related Art 
         [0004]    Mobile communication devices, such as cellular telephones, have become very common among the general public. With advances in technology, the costs of mobile communication equipment and services are continually being reduced. Mobile carriers offer various plans and packages and subscribers can pick among various carriers and plans so as to minimize their costs. 
         [0005]    It has become common for individuals to own and/or carry multiple mobile devices. For example, a person may have one mobile phone for business use and another mobile phone for personal use. Also, a person may subscribe to multiple plans with one carrier or plans with multiple carriers. For example, one plan or package may offer free incoming calls and another package or plan may offer low-cost outgoing calls. Additionally, some people carry multiple mobile phones to protect their privacy. In such cases, one mobile device may be used for calls to and from family and friends while the other is used for calls to and from the general public. 
         [0006]    The Global System for Mobile Communications (GSM) is one of the most popular standards for mobile phones in the world. One of the key features of GSM is the subscriber identity module (SIM), commonly known as a SIM card. The SIM is a detachable smartcard containing the user&#39;s subscription information and phonebook. This allows the user to retain his or her information after switching handsets. Alternatively, the user can also change plans or carriers while retaining the handset simply by changing the SIM card. Thus, a user can effectively have multiple mobile devices by possessing one handset and multiple SIMs. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention provides a mobile device that is adapted to receive first identification circuitry and second identification circuitry. The first identification circuitry is associated with a first network and the second identification circuitry is associated with a second network, which may be the same as or different from the first network. The mobile device includes means for simultaneously registering itself with the first and second networks using the first and second identification circuitry, respectively. The first and second identification circuitry may each comprise subscriber identity modules (SIMs). Thus, embodiments of the present invention effectively provide multiple mobile devices combined into a single unit. 
         [0008]    Embodiments of the present invention may include user preferences. An example of a user preference is a preferred SIM for outgoing calls. When the user physically places a call, the mobile device automatically uses the preferred SIM, whereby the call is placed through the preferred network using the preferred service plan. In some embodiments, the user may override the preference and place a call using the non-preferred SIM. Additionally, the user may specify exception preferences. For example, one SIM may be preferred for use during the day on weekdays while the other is preferred for use on weekends and during the evening on weekdays. 
         [0009]    Normally, the mobile device can receive calls at any time for either SIM. The mobile device may include a feature similar to call waiting that enables the mobile device to handle calls for both SIMs at the same time. Embodiments of the present invention allow the user to toggle back and forth between calls on the two SIMs. Embodiments of the present invention may include an auto-answering feature. According to the auto-answering feature, when a call to the non-preferred SIM is received, the calling party can automatically be advised to call back on the preferred number. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further purposes and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, where: 
           [0011]      FIG. 1  is a block diagram of an embodiment of a mobile device according to the present invention; 
           [0012]      FIG. 2  is a block diagram of a communication system including an embodiment of a mobile device according to the present invention; 
           [0013]      FIG. 3  is a block diagram of a typical cellular telephone system; 
           [0014]      FIG. 4  is an illustration of an embodiment of a user preference table according to the present invention; 
           [0015]      FIG. 5  is a flow chart of an embodiment of registration processing according to the present invention; 
           [0016]      FIG. 6  is a flow chart of an embodiment of call receiving processing according to the present invention; 
           [0017]      FIGS. 7A and 7B  comprise a flow chart of an embodiment of call placing processing according to the present invention; and, 
           [0018]      FIG. 8  is a flow chart of an embodiment of retry processing according to the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0019]    Referring now to the drawings, and first  FIG. 1 , an embodiment of a mobile device system according to the present invention is designated generally by the numeral  100 . Mobile device  100  includes a controller  101  that is programmed according to the present invention, as well as to perform other mobile device operations. Mobile device  100  includes a keypad  103  and the display  105 , each coupled to controller  101 . As is known to those skilled the art, keypad  103  includes various keys for entering telephone numbers and performing typical mobile device operations as well as operations according to the present invention. Display  105  may be a liquid crystal or other display commonly used in mobile devices. Mobile device  100  includes a speaker  107  and a microphone  109  coupled to controller  101 . Mobile device  100  includes a radio  111  coupled to controller  101 . Mobile device  100  includes a memory  113  coupled to controller  101 . Mobile device  100  may preferably be housed in any number of conventional cellular telephone cases. 
         [0020]    Mobile device  100  includes a first subscriber identity module (SIM) slot  115  and SIM slot  117  each coupled to controller  101 . Each SIM slot  115  and  117  is adapted to receive a SIM card. In  FIG. 1 , SIM slot  115  is coupled to a SIM card  119 . Similarly, SIM slot  117  is coupled to a SIM card  121 . As is known to those skilled in the art, existing cellular telephone units include a door that provides access to a SIM card and slot in the back of the unit. As will be apparent to those skilled in the art, the two SIM slots  115  and  117  may be accessible through a similar door. Although, the present invention is illustrated and described with respect to a mobile unit including two SIM cards, those skilled in the art will recognized that embodiments of the present invention may include more than two SIM cards. 
         [0021]      FIG. 2  as a high-level block diagram of a communication system  201  including a mobile device  100  according to the present invention. Communication system  201  includes a first mobile network  203  and a second mobile network  205 . Mobile networks  203  and  205  are typical networks associated with any of various mobile carriers. As will be described in connection with  FIG. 3 , mobile networks  203  and  205  may be global packet relay system (GPRS) networks, or any other mobile type of network. Mobile network  203  is coupled to a public switched telephone network (PSTN)  207  and the Internet  209 . Similarly, mobile network  205  is coupled to PSTN  207  and Internet  209 . Mobile device  101  is coupled wirelessly to mobile networks  203  and  205 . It should be recognized that mobile networks  203  and  205  may be the same network. 
         [0022]      FIG. 2  is a block diagram of a typical mobile network, such as mobile network  203  of  FIG. 1 . Mobile network  203  includes a packet radio service (e.g., GPRS, EDGE, CDMA) system  301 . Packet radio service system  301  enables a mobile device, such as mobile device  101 , to access both a data network, such as the Internet  209 , and a public switched telephone network (PSTN)  207 . An originating mobile switching center (MSC-O)  303  provides an interface mobile network  203  and PSTN  207 . In one embodiment where the packet radio service is GPRS, a home location register (HLR)  305  provides MSC-O  303  subscriber and location information for the mobile devices in its home area. A gateway mobile switching center (G-MSC)  307  is connected to MSC- 0   303  and a visitor location register (VLR)  309 . VLR  309  provides location information to HLR  305 . A servicing mobile switching center (MSC-S)  311  is connected to G-MSC  307  and a VLR  313 . VLR  313  provides location information to HLR  305 . MSC-S  311  is connected to a plurality of base stations, including base stations  315  and  317 , which use digital control channels (DCCHs) for paging and registration of mobile units and their respective areas. 
         [0023]    A gateway GPRS support node print (GGSN)  319  provides an interface between Internet  209  and mobile network  203 . A GPRS HLR  321  provides GGSN  319  with location and subscriber information. GGSN  319  and GPRS HLR  321  are in communication with a servicing GPRS support node (SGSN)  323 , which communicates with mobile devices in its area through a plurality of base stations, including base stations  325  and  327 . Base stations  325  and  327  use packet control channels (PCCHs) for paging and registration of mobile units in their respective areas. 
         [0024]      FIG. 4  illustrates a table  401  of user preferences according to an embodiment of the present invention. A user may set preferences whereby one SIM card will be used as the preferred or default SIM card for outgoing calls. Thus, table  401  includes a preferred entry  403 , which in the illustrated embodiment is denoted as SIM-A. A user may specify exceptions under which the other SIM card will be used. Thus, table  401  includes a date/Time exceptions  405 . In the illustrated embodiment, the other SIM card will be used for outgoing calls weekdays between 9 p.m. and 6 a.m. and all day on the weekends. In the embodiment of  FIG. 4 , the user may set an auto answer feature, as indicated by entry  407 . When the auto answer feature is on, incoming calls to the non-preferred SIM will be answered with a message instructing the calling party to call back on the number of the preferred SIM. Preference table  401  includes an override feature  409 , which enables the user to override the preferred SIM for a particular call. For example, when SIM-A is the preferred SIM, the user can press an override key and use the other SIM for making an outgoing call. It will be recognized that the preferences listed in the table of  FIG. 4  are only examples of preferences and features that may be made available in a mobile device according to the present invention. All features available in cellular phones and the like may be incorporated into mobile devices according to the present invention, as will be apparent to those skilled in the art. 
         [0025]      FIG. 5  is a flow chart of an embodiment of registration processing according to the present invention. Power up is initiated at block  501 . The mobile device controller checks preferences, as indicated at block  503 . Then, the mobile device searches for the preferred network, as indicated at block  505 . If, as determined at decision block  507 , the preferred network is found, the mobile device registers with the preferred network, as indicated at block  509 . If, as determined at decision block  507 , the preferred network is not found, the mobile displays a preferred network not found message and schedules a retry, as indicated at block  511 . Then, the mobile device searches for the non-preferred networks, as indicated at block  513 . If, as determined at decision block  515 , the non-preferred network is found, the mobile device registers with the non-preferred network, as indicated at block  517 . If, as determined at decision block  515 , the non-preferred network is not found, the mobile device displays a non-preferred network not found message and schedules a retry, as indicated at block  519 . If, as determined at decision block  521 , a retry is scheduled at block  511  and/or block  519 , the mobile device performs retry processing, as indicated generally at block  523  and described in detail with reference to  FIG. 8 . After registration and successful retry, if any, the mobile device is ready to make calls to and receive calls from both the preferred and non-preferred networks according to user preferences. 
         [0026]      FIG. 6  is a flow chart of an embodiment of call receipt processing according to the present invention. The mobile device receives a call, as indicated at block  601 . The mobile device checks the preferences, as indicated at block  603 . If, as determined at decision block  605 , the call is for the preferred SIM, the mobile device checks, at decision block  607 , if the user is using the other SIM. The embodiment illustrated in  FIG. 6  includes a feature similar to call waiting with which the mobile device may be used for simultaneous calls using both SIM&#39;s. If, as determined at decision block  607 , the mobile devices not using the other SIM, the mobile device displays a call received on preferred SIM message and rings the phone, as indicated at block  609 . 
         [0027]    Referring back to decision block  605 , if the call received is not for the preferred SIM, the mobile device determines, at decision block  611 , if auto answering is set. Auto answering is a mobile phone feature that automatically answers and performs some automated processing of a call. If auto answering is set, the mobile device delivers to the calling party a message to call back on the preferred SIM and disconnects, as indicated at block  613 . The message to call back may be a recorded voice announcement stored in the memory of the mobile device or other form of message such as a short message system (SMS) message. Other automated call processing may be performed if auto answering is set. For example, auto answering may be configured to send an SMS to the mobile device that there is an incoming call on the non-preferred SIM. The SMS may include such information is the identity of the calling party, the time of the call, etc. The calling party may also be able to record a voice message instead of calling back on the preferred SIM. If, as determined at decision block  611 , auto-answering is not set, the mobile device determines, at decision block  615 , if the mobile device is currently using the other SIM. If not, the mobile device displays a call received on the non-preferred SIM message and rings the phone, as indicated at block  617 . If, as determined at block  615 , the mobile device is currently using the other SIM for a call, the mobile device plays an audible alert, which may similar to a call waiting alert, to the user and displays a call received on the non-preferred SIM message, as indicated at block  619 . The mobile device then waits for the user to answer the call. The user can answer the call by pressing a button on the keypad in the same way that the user answers a call waiting call. If, as determined at decision block  621 , the user answers the call, the mobile device places one of the calls on hold and connects the other call, as indicated at block  623 . As indicated at decision block  625 , the user can toggle back-and-forth between the calls. 
         [0028]    Referring back to decision block  607 , if the user is using the other SIM for a call, which in this case is the non-preferred SIM, the mobile device plays an audible alert and displays a call received on the non-preferred SIM message, as indicated at block  627 . Then, processing proceeds to decision block  621 . 
         [0029]      FIGS. 7A and 7B  comprise a flow chart of outgoing call processing according to an embodiment of the present invention. As is typical in the cellular phone art, a user enters digits on the keypad and then presses a send button to make a call. The mobile device receives a send command, at block  701 . Then, the mobile device checks preferences, at block  703 . Embodiments of the present invention may include an override feature that enables the user to make a particular call on the non-preferred SIM. If, as determined at decision block  705 , override is set, processing proceeds to  FIG. 7B . If, as determined at decision block  705 , override is not set, the mobile device determines, at decision block  707 , if it is registered with the preferred network. If so, the mobile device places the call using the preferred SIM, as indicated at block  709 . If, as determined at decision block  707 , the mobile device is not registered with the preferred network, the mobile device determines, at decision block  711 , if it is registered with the non-preferred network. If not, the mobile device displays a not registered with either network message, as indicated at block  713 , and processing ends. If, as determined at block  711 , the mobile device is registered with the non-preferred network, but is mobile device displays a not registered with the preferred network message and prompts the user to place the call using the non-preferred SIM, as indicated at block  715 . Thus, the user may choose whether or not to use the non-preferred SIM to place the call. If, as determined at decision block  717 , the user chooses to place the call, the mobile device places a call using the non-preferred SIM, as indicated at block  719 . 
         [0030]    Referring to  FIG. 7B , if the user is chosen to override the preferred SIM, the mobile device determines, at decision block  721 , if the mobile device is registered with the non-preferred network. If so, the mobile device places call using the non-preferred SIM, as indicated at block  723 . If, as determined at decision block  721 , the mobile device is not registered with the non-preferred network, the mobile device determines, at decision block  725  if it is registered with the preferred network. If not, the mobile device displays a not registered with the network message, as indicated at block  727 . If, as determined at decision block  725 , the mobile device is registered with the preferred network, the mobile device displays a not registered with non-preferred network message and prompts the user to place a call using the preferred SIM, as indicated at block  729 . If, as determined at decision block  731 , the user elects to place the call, the mobile device places the call using the preferred SIM, as indicated at block  733 . 
         [0031]      FIG. 8  is an embodiment of retry processing indicated generally at block  523  of  FIG. 5 . If, as determined at decision block  801 , the preferred network is scheduled for retry, the mobile device searches for the preferred network, at block  803 . If, as determined at decision block  805 , the preferred network is found, the mobile device registers with the preferred network, at block  807 . If, as determined at decision block  805 , the preferred network is not found, the mobile device determines, at decision block  809 , if the non-preferred network is scheduled for retry. If not, processing returns to block  801 . If the non-preferred network is scheduled for retry, the mobile device searches for the non-preferred network, as indicated at block  811 . If, as determined at decision block  813 , the non-preferred network is found, the mobile device registers with the non-preferred network, at block  815 , and processing returns to block  801 . 
         [0032]    Returning to decision block  801 , if the preferred network is not scheduled for retry, the mobile device determines, at decision block  817 , if the non-preferred network is scheduled to retry. If so, the mobile device searches for the non-preferred network, as indicated at block  819 . If, as determined at decision block  821 , the non-preferred network is found, the mobile device registers with the non-preferred network, at block  823 , and retry processing ends. 
         [0033]    From the foregoing, it will be apparent to those skilled in the art that systems and methods according to the present invention are well adapted to overcome the shortcomings of the prior art. While the present invention has been described with reference to presently preferred embodiments, those skilled in the art, given the benefit of the foregoing description, will recognize alternative embodiments. Accordingly, the foregoing description is intended for purposes of illustration and not of limitation.