Abstract:
Proximity of a mobile phone to a preferred phone is detected by radio frequency or Bluetooth equipped device, triggering automatic forwarding of calls for the mobile phone to the preferred telephone number. Automatic forwarding without user intervention can facilitate use of hands-free devices in vehicles and allow receipt of phone calls to mobile phone on regular lines in a home or office situation.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Technical Field  
           [0002]    The present invention relates generally to mobile telephony, and in particular to ease of use. Still more particularly, the present invention provides a method and apparatus for automatically forwarding phone calls to a preferred second phone when the mobile phone is in the vicinity of the second phone.  
           [0003]    2. Description of Related Art  
           [0004]    The use of mobile phones is escalating worldwide, and as in any developing technology, new capabilities create problems that are unforeseen. For instance, the number of accidents caused by drivers using mobile phones has resulted in legislation in many states which prohibits the use of mobile phone by drivers unless they are operated hands free. While hands free operation can be achieved by an earpiece and microphone worn by the user, many persons prefer a speaker and microphone permanently installed in the vehicle, with either a docking station for their hand held mobile phone or a separate phone.  
           [0005]    Thus, it is not uncommon for users to have a regular phone at home, a mobile phone which they carry with them, and a hands-free setup in their car. Several inconvenient or distracting situations can be caused by this proliferation of phone sites. For instance, the user may forget to use the docking mechanism in his car until a call is received or may leave the phone in the docking mechanism when they exit the vehicle. If the user has a separate phone for the car, the user may wish to receive calls on that phone when driving, and likewise to use a regular phone when at home. Therefore, it would be desirable to have this capability automatically, without requiring user intervention.  
         SUMMARY OF THE INVENTION  
         [0006]    In the disclosed invention, a low-power transmitter is used to notify a handheld mobile phone that it is in proximity to a phone whose use is preferred over that of the mobile phone itself, such as the user&#39;s home phone. When this happens, calls received by the mobile phone are automatically forwarded to the preferred phone without user intervention, and, if the mobile phone is capable of going into a standby mode, it will do so. When the user carries the mobile phone out of the vicinity of the preferred phone, the transmitter signal is lost and the forwarding function and standby mode are ended.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]    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 objectives 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, wherein:  
         [0008]    FIGS.  1 A- 1 B show a graphical representation of the operation of the invention in accordance with a preferred embodiment.  
         [0009]    [0009]FIG. 2 depicts the connections between components in accordance with a preferred embodiment of the invention.  
         [0010]    [0010]FIG. 3 shows a flowchart of events to implement an embodiment of the innovative telephone forwarding when the mobile phone is equipped with circuitry to request the forwarding.  
         [0011]    [0011]FIG. 4 shows a block diagram of mobile phone system.  
         [0012]    [0012]FIG. 5 depicts the connections between components in accordance with an alternative preferred embodiment of the invention.  
         [0013]    [0013]FIG. 6 shows a flowchart of events to implement an alternative embodiment of the innovative telephone forwarding.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0014]    With reference now to the drawings and with particular reference to the graphical explanation of FIGS. 1A and 1B, the overall operation of the invention in accordance with a preferred embodiment will now be described. The user who carries mobile phone  110  prefers to receive calls on phone  130  whenever possible. Phone  130  can be a phone which is connected to a wire based system, e.g., at the user&#39;s home or office, or it can be a wireless phone, which is, for example, permanently installed in the user&#39;s vehicle. Phone  130  is equipped with, or has associated with it, a transmission device (not specifically shown). The range covered by the transmitter is depicted by the circle  120  which surrounds phone  130 .  
         [0015]    In FIG. 1A, when mobile phone  110  is outside the range  120  of the transmitter, each of phones  110  and  130  will receive calls sent to their own number, shown by their separate ringing. In FIG. 1B, however, mobile phone  110  has entered the range  120  of the transmitter associated with preferred phone  130 , so calls to phone  110  are being forwarded to phone  130 , which accepts calls for both numbers.  
         [0016]    The specific protocol used to implement the system described can vary, but several exemplary methods will now be discussed. With reference to FIG. 2, an exemplary embodiment is shown in which mobile phone  230  is to be forwarded to a preferred phone  240  that is tied into the public switched telephone network (PSTN). In this embodiment, the mobile phone initiates a request to the cellular system to forward the phone. A flowchart showing the steps is shown in FIG. 3, which will be discussed at the same time as FIG. 2. Preferred phone  240  can be, for example in the user&#39;s home, an extension at an office, or anywhere the user desires. Mobile phone  230  communicates through cellular system  210 , while preferred phone  240  is connected to PSTN system  250 . Cellular system  210  and PSTN  250  are also connected to each other to allow communications between mobile users and PSTN users. While users are generally most familiar with the voice communications over cellular system  210  and PSTN  250 , each of these systems also maintain overhead communications with their respective phones. In PSTN  250 , this overhead includes monitoring whether the phone is on-hook or off-hook and handling features such as call forwarding or call waiting. Cellular system  210  likewise conducts overhead, such as locating the cell phone or passing a call off to another cell as the user travels, using separate overhead channels.  
         [0017]    In this embodiment, transmitter  220  is a low power RF transmitter. When transmitter  220  is installed, it is programmed with the phone number of preferred phone  240 . This preferred phone number is then transmitted as part of its signal. Mobile phone  230  is equipped to receive signals in the frequency of transmitter  220  and is programmed to recognize a signal meant for it. When mobile phone  230  comes within the range of transmitter  220 , mobile phone  230  receives the transmitted signal (step  310 ). In step  320 , phone  230  sends an overhead message to cellular system  210  requesting forwarding of calls to preferred phone  240  (step  320 ) and passing on the appropriate phone number for forwarding. Once this request is received, the cellular system stores the number for forwarding (step  330 ); thereafter, phone calls to phone  230  will be routed by cellular system  210  through phone system  250  to preferred phone  240 . When the user carries mobile phone  230  outside of the range of transmitter  220 , mobile phone  230  recognizes that it is no longer receiving a signal from the low-powered transmitter (step  340 ). Mobile phone  230  then transmits a request to cellular system  210  on an overhead channel to remove the forwarding request (step  350 ). Once cellular system  210  has removed the forwarding (step  360 ), the algorithm is complete.  
         [0018]    [0018]FIG. 4 is a block diagram of the cellular system  210 , which was seen in FIG. 2. In cellular system  210 , a mobile switching center  410  controls a region, such as a large city. Mobile switching center  410  communicates with a number of base station controllers  440 , although only one is shown here. In turn, each base station controller  410  controls one or more base transceiver stations  450 . Each base transceiver station  450  handles the communications with mobile phones  470  which are within the cell  460  corresponding to that base transceiver station  450 . Mobile switching center  410  stores information for those phones which are enrolled in its local area in the home location register. This information can include the identification number of the mobile phone, billing information, and information regarding special services. Likewise, mobile switching center  410  stores information regarding phones which are not enrolled with it, but which are in its service area, in the visitor location register  430 . Location registers  420  and  430  are used when a call is placed to a specific mobile phone. When a forwarding request is sent to a base transceiver station  450 , the request and the forward-to number are passed to base station controller  440  and to mobile switching center  410 . The information will be stored in the home location register  420  at the mobile switching center  410  that is “home” for that mobile phone  230 . This information is referenced whenever mobile phone  230  is called so that stored forwarding information can be used.  
         [0019]    An alternate embodiment of the phone-forwarding is shown in FIG. 5, where preferred phone  540  is a hands free mobile phone installed in the user&#39;s automobile. This figure will be discussed in conjunction with FIG. 6, which explains an alternate method of handling the transfer. In this example, preferred phone transmitter  220  uses Bluetooth (TM) technology to communicate with mobile phone  230 , which also includes Bluetooth capabilities. Bluetooth refers to a wireless standard which operates in the 2.4 Ghz band. Bluetooth products can have a range of 10 to 100 meter, depending on the strength of the signal, with many new applications being developed for close proximity applications, such as automatic, cordless updating between a home computer and handheld notebook.) Bluetooth does not require line of site capabilities, so mobile phone  230  can remain in a briefcase and still communicate with preferred phone transmitter  220 .  
         [0020]    In this embodiment, when mobile phone  230  is in proximity with transmitter  220  mobile phone  230  receives a signal to forward calls (step  610 ). The mobile phone  230  and transmitter  220 , exchange a “handshake” greeting, verifying that they are intended to work together. The identity (ID) of mobile phone  230  is then passed (step  620 ) to preferred phone  340  with its hand-free operation, while mobile phone  230  effectively removes itself from the system and will no longer respond to calls to its ID. The ID number is then passed from transmitter  220  to preferred cellular phone  540 , which installs this number as its own ID (step  630 ). While mobile phone  230  remains in proximity to preferred phone  340 , when cellular system  210  searches for mobile phone  230 , cellular system  210  finds the identity (ID) of phone  230  in preferred phone  340  and will transmit the call to phone  340 . Because of the transfer of identity in this embodiment, it is important that this be a secure transmission, preferably using an encryption scheme. When the user takes mobile phone  230  out of range of transmitter  220  so that the signal is no longer received (step  640 ), mobile phone  230  resumes communications using its original system identity, while phone transmitter  220  passes on the message to preferred cellular phone  540  to stop responding with the transferred ID (step  650 ). This method can be used with phones which comply with the standards set by Global System for Mobile Communication (GSM), as well as non-GSM phones. It would be possible with this embodiment to make preferred phone  340  a phone without a system ID of its own. For instance, this arrangement would allow car rental agencies to supply hands-free capabilities to a user without incurring liability for charges to the installed phone. Rather, the hands-free phone would take on the identity of any mobile phones equipped to communicate with it.  
         [0021]    Other capabilities can be incorporated with this application. For instance, the ability to override the transfer of calls can be programmed into a button on the mobile phone  230 . This can be useful, for instance, when the preferred phone is currently engaged by another person and the user does not wish to miss calls.  
         [0022]    Additionally, a single transmitter can be programmed to recognize different mobile phones associated with it and to transfer each mobile phone to a different extension. This could be utilized in an office where multiple employees utilize mobile phones for business or in homes where both spouses carry mobile phones.  
         [0023]    The description of the present invention has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiment was chosen and described in order to best explain the principles of the invention, the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.