Abstract:
A mobile device and method in one example for automatically redialing a dialed number when a call has failed is provided. The mobile device stores the dialed number when the call is initially being placed. If the call fails, the mobile device determines if a call retry service should be invoked. If so, the mobile device determines whether a call retry system has already been enabled. If the call retry system has been enabled, the mobile device will continually and automatically call the dialed number until a terminating party at the dialed number answers or a selectable time limit has expired. When the terminating party answers the call, the mobile device rings so that a subscriber of the mobile device may answer the ring and connect the call. The mobile device may also detect if the dialed number is an emergency number or non-emergency number. A recorded message recorded by the subscriber may be automatically played to the terminating party if the subscriber does not answer the ring. Alternatively, or in addition to, a default recorded message may be played to the terminating party if the subscriber does not answer the ring.

Description:
TECHNICAL FIELD 
       [0001]    The present invention is directed to telecommunications systems and especially to a system and method which automatically attempts to establish a call from a cellular telephone that failed. 
       BACKGROUND 
       [0002]    In recent years the use of mobile phones has become more common. As mobile phone use has become more common, people are more frequently using their mobile phones to contact friends, business associates, family members, and emergency services. Unfortunately, mobile phone users are sometimes confronted with failed calls when attempting to contact another party. 
         [0003]    Mobile phone calls may fail for one of any number of reasons including lack of service, cell site unavailability, or a lack of radio frequency coverage. When a subscriber places a non-emergency mobile phone call that fails, it would be convenient for a subscriber to be able to automatically reconnect and leave a voice message for the intended party. This need is heightened when the subscriber places an emergency call. If the emergency call is made because of a medical emergency, the subscriber may become incapacitated before service is available to complete the call. If the subscriber becomes incapacitated between the times the call fails and the service is restored, the subscriber will not be able to reinitiate the emergency call. The subscriber is therefore unable to notify the proper authorities and may consequently be unable to obtain emergency assistance. 
         [0004]    Thus a need exists to provide a way to leave a voice message and automatically connect a call when a wireless phone call fails. A further need exists to provide emergency assistance access from a wireless phone when an initial emergency call fails. There is a further need to provide emergency assistance access from a wireless phone when an initial emergency call fails and the subscriber subsequently is unable to redial the emergency assistance number. 
       SUMMARY 
       [0005]    The invention in one implementation encompasses a method of attempting to connect a failed call from a mobile device, the method comprising the steps of storing a dialed number of the failed call; determining if a call retry service should be invoked; and attempting to connect the failed call by automatically redialing the dialed number if the call retry service is invoked. The method may further comprise the steps of determining whether the dialed number is an emergency number; and determining whether an emergency retry service should be invoked if the dialed number is an emergency number. The dialed number may be determined to be an emergency number by comparing the dialed number and a list of emergency numbers, and indicating an emergency number has been dialed when there is a match between the dialed number and a number in the list of emergency numbers. 
         [0006]    The invention in one implementation encompasses a mobile device for placing a call comprising a user interface for inputting a dialed number by a subscriber. A call failure detector determines whether the call to the dialed number failed. A call retry service detector determines whether a call retry service is enabled. A call generator repeatedly generates a call to the dialed number in response to the call retry service detector. 
         [0007]    The mobile device may further comprise an emergency call memory for storing a list of emergency numbers. A comparator compares the list of emergency numbers to the dialed number and determines whether the dialed number is one of the list of emergency numbers. The call retry service detector may comprise an emergency retry service detector which determines whether the emergency retry service is enabled. The mobile device may further comprise an emergency retry service rejection detector for prompting whether a subscriber of the mobile device wishes to reject the emergency retry service and for determining whether the emergency retry service is rejected. The call retry service detector may comprise a non-emergency retry service detector for determining whether a non-emergency retry service is enabled. 
         [0008]    A further implementation of the invention encompasses a system for attempting to connect a call that has failed. The system comprises a mobile device for calling a dialed number, for storing a list of emergency numbers, for determining whether the call to the dialed number has failed, and for automatically redialing the dialed telephone number if the dialed telephone number is on the list of emergency numbers and the call has failed. A call receive system receives the call from the mobile device. The mobile device may further comprise a message recorder for recording a recorded message, a message memory for storing the recorded message; and a message player for repeatedly playing the recorded message when the call is completed to the dialed number. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0009]    Features of example implementations of the invention will become apparent from the description, the claims, and the accompanying drawings in which: 
           [0010]      FIG. 1  is a representation of one implementation of a call retry method that comprises determining if an emergency number is dialed and determining if an emergency retry service should be invoked, or if a non-emergency retry service should be invoked. 
           [0011]      FIG. 2  is a representation of one implementation of a method for retrying an emergency call. 
           [0012]      FIG. 3  is a representation of one implementation of a method for retrying a non-emergency call. 
           [0013]      FIG. 4  is a representation of one implementation of a method for continuously trying to connect a wireless call until a call connection is made. 
           [0014]      FIG. 5  is a functional block diagram of an embodiment of a telecommunications network with a wireless device used to retry an emergency call. 
           [0015]      FIG. 6  is a functional block diagram of an embodiment of a wireless device used to retry an emergency call. 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    Turning to  FIG. 1 , a call retry method  10  in one example for detecting when a call has failed, for determining if a non-emergency number or an emergency number has been dialed and determining if an emergency retry service or a non-emergency retry service should be invoked. An illustrative description of the call retry method  10  is presented for explanatory purposes. 
         [0017]    A wireless, or mobile, device begins in a ready state  20 . In this state the mobile device may attempt to initiate a call or receive a call. It will be apparent to one of skill in the relevant art that a mobile device may be a cellular phone, a satellite phone or any other electronic device that has the capability to make a wireless call. The subscriber attempts to make a call  30  to a telephone number. The call fails  30  for any number of reasons. For example, the call may fail because the mobile device is not in radio frequency coverage of a telecommunications network, there may be a radio frequency anomaly that prevents the mobile device from receiving sufficient signal strength from the telecommunications network, or the telecommunications network may be temporarily unavailable. These are examples of why an attempted call may fail. It will be readily apparent to those skilled in the relevant art that this is not an exhaustive list of why a call may fail and that there are numerous other reasons why a call may fail. 
         [0018]    The telephone number dialed, i.e. the dialed number, of the failed call is compared with a list of emergency telephone numbers  40 . The call retry method  10  then determines whether a call retry method should be invoked, and more particularly, whether an emergency retry method or a non-emergency retry method should be invoked. For purposes of this disclosure the call retry method comprises the emergency retry method and the non-emergency retry method. If the dialed number matches an entry in the list of emergency telephone numbers  50 , an emergency retry method is invoked  60 . If the dialed number does not match any entry in the list of emergency numbers  50 , then a non-emergency retry method  70  is invoked. The entries in the list of emergency numbers may be any designations which are sufficient to identify whether the dialed number is an emergency or non-emergency number. The entries may for example be actual emergency telephone numbers or other designations which map to emergency telephone numbers. Once the emergency retry method  60  establishes communications with the dialed number, the call retry method  10  enters the call complete state  80 . Similarly, once the non-emergency retry method  70  establishes communications with the dialed number, the call retry method  10  enters a call complete state  80 . 
         [0019]    Turning to  FIG. 2 , an illustrative description of an emergency retry method  60  is presented for explanatory purposes. In performing an emergency retry, the emergency retry method  60  determines if the emergency retry service is enabled  90 . If the emergency retry service is not enabled, then the emergency retry method  60  prompts the subscriber whether to reject the emergency retry service  95 . If the subscriber rejects the emergency retry service  100 , the emergency retry method  60  ends  115 . If the subscriber does not reject the emergency retry service  100  or the emergency retry service is enabled at  90 , the emergency retry method  60  prompts the subscriber whether to record an emergency message  110 . 
         [0020]    If the subscriber chooses not to record an emergency message  120 , a retry time limit is set  125  and the continuous retry method is invoked  130 . The retry time limit is a time duration during which the mobile device is allowed to try to connect a failed call. Once this time limit is exceeded, the mobile device stops attempting to connect the failed call. In the case of an emergency call, such as an emergency call performed by the emergency retry method  60 , the mobile device may try to connect the call without time limits. The value of the retry time limit in the emergency retry method  60  is set to an initial value which indicates that there is no time limit to establishing the emergency call. For example, the time limit could be initialized to 0 to indicate there is no time limit to establishing the call. If the subscriber chooses to record an emergency message  120 , the emergency message is recorded  140 , the retry time limit is set  125 , and the continuous retry method is invoked  130 . 
         [0021]    Turning to  FIG. 3 , an illustrative description of a non-emergency retry method  70  is presented for explanatory purposes. In performing a non-emergency retry, the non-emergency retry method  70  determines if the non-emergency retry service is enabled  150 . If the non-emergency retry service is not enabled  150 , the non-emergency retry method ends  160 . If the non-emergency retry service is enabled  150 , the non-emergency retry method  70  prompts the subscriber whether to record a message  170 . 
         [0022]    If the subscriber chooses not to record a message  180 , the subscriber is prompted for a retry time limit  190 , and the continuous retry method  200  is invoked. If the subscriber chooses to record a message  180 , the message is recorded  210 , the subscriber is prompted for a retry time limit  190 , and the continuous retry method  200  is invoked. 
         [0023]    Turning to  FIG. 4 , an illustrative description of the continuous retry method  200  is presented for explanatory purposes. The mobile device attempts to establish a call  220 . The mobile device may decide to attempt to establish a call by originating a call upon a successful registration attempt. Alternatively, the mobile device may decide to attempt to establish a call based on the expiration of a timer mechanism. Using the registration process or timer mechanism is only two of many ways the mobile device may decide to attempt to establish an emergency call. Upon attempting to connect the call  220 , the continuous retry method  200  determines if the retry timer has expired  230 . If the retry timer has expired  230  the continuous retry method ends  240 . If the retry timer has not expired  230  the continuous retry method  200  determines if the call is connected  245  to the terminating party. Those of ordinary skill in the art would readily appreciate that the terminating party is the party that is called by the party that is originating the call. If the call is not connected  245  the continuous retry method attempts to connect the call again  220 . 
         [0024]    Once the call is connected  245  to the terminating party, the continuous retry method  200  rings the mobile  250 . If the subscriber answers the mobile  260  the continuous retry method  200  ends  240 . When the subscriber answers the ringing mobile device, the mobile device stops ringing, and the subscriber talks to the terminating party. 
         [0025]    If the subscriber does not answer the mobile device  260 , the mobile device plays a default message to the terminating party  270 . If the subscriber recorded a message, the recorded message is played to the terminating party or, alternatively, the recorded message is played along with the default message  270 . The default message and the recorded message are repeated  280  until either the subscriber answers the ringing mobile device or the terminating party disconnects the call. 
         [0026]    Turning to  FIG. 5 , an exemplary block diagram  300  comprises a mobile device  310  communicatively connected to a terminating party  320  via a telecommunications network  330 . The subscriber uses the mobile device  310  to attempt a call to the terminating party  320  via the telecommunications network  330 . It will be readily apparent to one of ordinary skill in the applicable art that the invention may be practiced with any number of telecommunications networks. 
         [0027]    Finally turning to  FIG. 6 , an illustrative description of the mobile device  310  is shown for explanatory purposes. A user interface  340  is a device used to retrieve information and output information to the subscriber. The user interface  340  may be, for example, comprised of one or more of a key-pad input, a screen, a microphone, or a speaker. The screen or speaker may be used to output information to the subscriber while the key-pad or microphone may be used by the subscriber to input information into the mobile device  310 . The subscriber enters a dialed number into a digit input  350  via the user interface  340 . The digit input  350  passes the dialed number to a comparator  360 . 
         [0028]    The comparator  360  stores the dialed number while the mobile device  310  attempts to establish a call. A call failure detector  370  signals the comparator  360  when a call attempt has failed. The comparator  360  then compares the dialed number against a list of emergency numbers contained in an emergency call memory  380 . If the dialed number does not match a telephone number in the emergency call memory  380 , the comparator  360  notifies a non-emergency retry service detector  390  that a non-emergency number was dialed. If the non-emergency retry service is enabled, the non-emergency retry detector  390  informs a message recording detector  400  that the subscriber invoked the non-emergency retry service. If the dialed number matches a telephone number in the emergency call memory  380  the comparator  360  notifies an emergency retry service detector  410  that a match occurred. The emergency retry service detector  410  determines whether the emergency retry service is enabled and provides an emergency retry service rejection detector  420  with the enablement status of the emergency retry service. The emergency retry service rejection detector  420  prompts the subscriber whether to reject the emergency retry service. If the subscriber does not reject the emergency retry service, then the emergency retry service rejection detector  420  notifies the message recording detector  400  that the subscriber invoked the emergency retry service. 
         [0029]    The message recording detector  400  then prompts the subscriber if a message should be recorded. If the subscriber decides to record a message a message recorder  430  is notified. The subscriber enters a voice message via the user interface  340  to the message recorder  430  which stores the message in a message memory  440 . 
         [0030]    A default message may be stored in a default message memory  450 . The default message memory  450  may hold an emergency default message and a non-emergency default message. These messages may be pre-programmed into the default message memory  450 , or they may be entered via the user interface  340  by the manufacturer, service provider or other vendor of the mobile device. A default message recorder  460  records the default messages and stores them in the default message memory  450 . 
         [0031]    The message recorder  430  notifies a call generator  470  when it has finished recording a message from the subscriber. The call generator  470  attempts to establish a call after an initial call fails. The attempt to successfully establish the call may be associated with a successful registration of the mobile device, with the expiration of a timer, or when adequate signal strength is detected by the mobile device  310 . When the call generator  470  determines that a call to the terminating party has been successfully established, the call generator  470  notifies a default message player  480  and a recorded message player  490 . The default message player  480  plays the default emergency message to the terminating party  320 . If there is a recorded message in the message memory  440 , the message player  490  plays the recorded message to the terminating party  320 . Either of the default message or the recorded message may be played to the terminating party  320  or, alternatively, both the default message and the recorded message may be played to the terminating party  320 . 
         [0032]    The mobile device  310  in one example employs one or more computer-readable signal-bearing media. The computer-readable signal-bearing media store software, firmware and/or assembly language for performing one or more portions of one or more implementations of the invention. Examples of a computer-readable signal-bearing medium for the mobile device  310  may comprise recordable data storage medium of the message memory  450  and the default message memory  460 . The computer-readable signal-bearing medium for the mobile device  410  in one example comprise one or more of a magnetic, electrical, optical, biological, and atomic data storage medium. For example, the computer-readable signal-bearing medium may comprise floppy disks, magnetic tapes, CD-ROMs, DVD-ROMs, hard disk drives, and electronic memory. 
         [0033]    The steps or operations described herein are just for example. There may be many variations to these steps or operations without departing from the spirit of the invention. For instance, the steps may be performed in a differing order, or steps may be added, deleted, or modified. 
         [0034]    Although example implementations of the invention have been depicted and described in detail herein, it will be apparent to those skilled in the relevant art that various modifications, additions, substitutions, and the like can be made without departing from the spirit of the invention and these are therefore considered to be within the scope of the invention as defined in the following claims. For example, a number of the steps described herein may be implemented in software or hardware or any combination thereof.