KR20020003862A - System and method for facilitating wireless call connections in emergency situations - Google Patents

Abstract

System and method for facilitating wireless call connection with emergency services (10). The system includes a mechanism for attempting to make a call to an emergency call center via a wireless service provider. The system monitors the validity of the service 14 provided by the wireless service provider and automatically completes the call 16 when the service is valid or valid. In a particular embodiment, the system includes software for searching for wireless service 18 where emergency calls can be made. The system repeatedly dials the telephone number to the emergency call center until the call is completed. In a particular embodiment, the software for repeatedly dialing 911 includes silent-redialing 30 software.

Description

SYSTEM AND METHOD FOR FACILITATING WIRELESS CALL CONNECTIONS IN EMERGENCY SITUATIONS

Background of the Invention

I. Background of the Invention

The present invention relates to a wireless communication system. In particular, the present invention relates to a system for facilitating emergency call connections in a cellular communication system.

II. Description of the related technology

As cellular telephone usage has increased, so has the dependence on cellular telephones to obtain emergency services. Typically, a wireless telephone user dials 911 to contact an emergency call center. If the call is in a spotty coverage area, such as an area with a deep fade, the user must continue 911 dialing until the call connects. Continuous redialing of the 911 for connection is undesirable in time critical emergency situations and may result in injury or injury to the user.

Therefore, the Federal Communications Commission (FCC) recently enacted a law requiring wireless service providers to implement methods to facilitate cellular telephone emergency call connections.

Accordingly, there is a need in the art for an improved system and method for facilitating wireless call connections in emergency situations.

Summary of the Invention

The need in the art is introduced by a system to facilitate the wireless call connection to the emergency call center of the present invention. In an exemplary embodiment, the present system is employed for use with a cellular telephone and includes a mechanism for attempting to make a call to an emergency call center via a wireless service provider. The system monitors the validity of the service provided by the wireless service provider and automatically completes the call when the service is valid or valid.

In a particular embodiment, the system includes software for searching for a wireless service in which an emergency call can be made. The system dials the telephone number of the emergency call center repeatedly until the call is completed.

Brief description of the drawings

1 is a flow chart of a method for facilitating wireless call connection to an emergency call center of the present invention.

FIG. 2 is a more detailed view of the method of FIG. 1.

3 is a diagram of a cellular telephone constructed in accordance with the teachings of the present invention for implementing the method of FIG.

4 is a diagram illustrating various states of the display screen of the cellular telephone of FIG. 3 when the cellular telephone in various states circulates according to the method of FIG.

Disclosure of the Invention

While the present invention is described herein in terms of exemplary embodiments for particular applications, it should be understood that the present invention is not limited thereto. Those skilled in the art having access to the lessons provided herein will recognize additional modifications, applications, and embodiments within the scope of the present invention and additional fields of the invention in which the present invention has significant utility.

1 is a flowchart of a method 10 for facilitating a wireless call connection to an emergency call center of the present invention. In a preferred embodiment, the unique method 10 is executed in software operating on a cellular telephone, described more fully below.

Initially, in step 11, the user of a cellular or wireless telephone employed for use with the present invention, dials '911' and 'Enter' or on a cellular telephone, as discussed more fully below. Press 'Send'.

Next, in step 12, the speaker volume of the cellular telephone is set to maximum. Subsequently, in the service-checking step 14, the cellular telephone checks for any valid wireless service provided by the wireless service provider. If the service is found, control passes to call-generating step 16, where the cellular phone automatically attempts to 911 dial and connect to the emergency call center. If no wireless service is found in the service-checking step 14, control transfers to the service-searching step 18 where the cellular telephone continues the service search until the service is found, i.e., obtained. The cellular telephone searches for a frequency, or channel, in the preferred roaming list (PRL) stored in the cellular telephone's memory. If the channel contains a known code division multiple access (CDMA) signal, then the phone assumes that the service has been successfully obtained.

If the wireless service is obtained in the service-search step 18, control passes to the call-generating step 16. In the call-generating step 16, if the emergency 911 call fails, i.e., dropped or never formed, control passes to the service-checking step 14, the service-search step 18, and the call-generating step 16. Return to the service-checking step 14 to form a loop with a.

The loop is activated when method 10 is completed. The method is completed when the service is obtained, the battery of the cellular phone is exhausted, or when the user cancels the method 10. The method 10 is canceled by turning off the cellular telephone or pressing the END key on the cellular telephone.

If the method 10 is completed, and an emergency call is connected or made, and subsequently a connecting or originating call is faded or dropped, the cellular telephone automatically restarts the method 10, so that control is performed. It moves to the checking step 14.

The novel design of the present invention allows the user to save valuable time and attention that may be required to obtain emergency services via a cellular telephone in an emergency situation.

2 is a more detailed view of the present method 10 of FIG. Service-checking step 18 includes a callback-mode-checking step 20, a looking-for-service step 22, an emergency-search-continue step 24, and an emergency-service-loss step. (26). The call-occurrence step 16 includes a call-emergency-911 step 288 and a silent redial step 30.

After the volume setting step 12, the service-checking step 14 determines whether the service is currently valid. If no service is currently valid, control passes from service-search step 18 to callback-mode-checking step 20. Callback-mode-checking step 20 checks if the cellular phone is currently in callback mode. In callback mode, if the call does not answer after a certain number of rings, the cellular telephone will automatically answer the incoming call from the emergency call center. A more detailed discussion of the emergency callback mode is provided in the "SYSTEM AND METHOD FOR AUTOMATICALLY ANSWERING INCOMING EMERGENCY CALLS TO A WIRELESS PHONE" filed Feb. 9, 1999, filed U.S. Patent Application Serial No. 09 / 246,467. Used for reference.

If the cellular phone is in callback mode, control is performed in the service-search phase (18) in which the cellular telephone continues the wireless service search on the same system where the cellular telephone successfully issued an emergency call that was dropped before the call entered the call state. The emergency-service-loss phase is moved to 26. In the emergency-service-loss phase 26, the cellular telephone displays a message on the cellular telephone screen specifying that emergency services are lost and the cellular telephone continues the emergency services search, as discussed more fully below. do. Emergency-service-loss phase 26 continues until wireless service is obtained or until phase 26 is canceled by the user of the cellular telephone or canceled due to lack of cellular telephone battery power. If the service is obtained in the emergency-service-loss phase 26, control is transferred from the call-occurrence phase 16 to the call-emergency-911 phase 28.

If the cellular phone is not in callback mode determined in callback-mode-checking step 20, control passes to service-searching step 22, where the cellular phone continues with any possible wireless service search to which the emergency call center is connected. do. In the service-searching step 22, a message is displayed on the cellular telephone screen informing the user that the cellular telephone is currently seeking emergency services. If the service is not obtained within one minute period, control passes to the emergency-search-continue step 24. In the emergency-search-continue step 24, the cellular telephone continues the emergency service search and displays a message on the cellular telephone screen informing the user that the cellular telephone is continuing the emergency service search. Within seven seconds, if no wireless service is obtained in the emergency-search-continue step 24, control returns to the service-search step 22. FIG. If service is obtained in the service-searching step 22 or in the emergency-search-continue step 24 or in the emergency-search-loss step 26, control is transferred from the call-emergency step 16 to the call-emergency-911 step ( 28).

In a call-emergency-911 step 28, the cellular phone displays a message on the cellular phone screen informing the user that the sacellular phone is currently calling 911. Control is immediately transferred to the silent-redialing step 30 where the cellular phone automatically dials 911. If the 911 call was successfully formed, i. E. Completed, the method 10 is completed. Otherwise, control returns to the service-checking step 14.

The present invention provides an effective way for a wireless telephone to redial an emergency number without user intervention in an unreliable service coverage area. This ensures that the wireless phone maximizes the ability to obtain emergency services even in situations where the user of the phone becomes unconscious.

3 is a diagram of a cellular telephone 50 constructed in accordance with the teachings of the present invention for implementing the method 10 of FIG. 1. The cellular telephone 50 includes an antenna 52 connected to the duplexer 54. The duplexer 54 is connected to the transceiver circuit 56, and the transceiver circuit 56 is connected to the computer 58. Computer 58 is connected to data interface adapter 60, voice encoding and decoding circuitry 62, keypad 64, and screen 66. Speech encoding and decoding circuitry 62 is connected to microphone 68 and speaker 70.

In operation, antenna 52 transmits and receives signals via duplexer 54. Duplexer 54 facilitates sharing the resources of antenna 52 between transmit and receive functions. The transceiver 56 includes circuitry for transmitting signals, such as voice signals or service negotiation signals, encoded via the antenna 52 and duplexer 54. The transceiver 56 also includes receiving circuitry for receiving signals, such as service negotiation messages or encoded voice signals, via other telephones, base stations, or mobile switching centers. The transceiver 56 also includes downconversion circuitry required to convert the received signal into a digital baseband signal in preparation for processing via the computer 58. In addition, the transceiver circuit 56 includes an upconversion circuit that is required to convert the transmission signal from the digital baseband signal to the radio frequency signal in preparation for transmission via the antenna 52.

The user can initiate the call by dialing the number via keypad 64. Computer 58 negotiates a service connection with a valid wireless service provider via transceiver circuit 56, duplexer 54, and antenna 52. When the service is formed, the user's voice is input into the microphone 68 and encoded by the voice encoding and decoding circuit 62, the computer 58, the transceiver circuit 56, the duplexer 62, and the antenna ( 52). Similarly, the received voice message is decoded by the voice encoding and decoding circuit 62 and output as voice via the speaker 70.

The user of the cellular telephone 50 can dial an emergency service such as 911 via the keypad 64. Software designed in accordance with the method of the present invention and operating on the computer 58 determines that the call is an emergency call and discloses the method of the present invention. Software for executing the method of the present invention on computer 58 can be developed by one of ordinary skill in the art without departing from the scope of the present teachings and without undue experimentation. The software may include routines for each step of the method of FIG. For example, call generation step 16 may employ silent-redialing software known in the art. The computer displays a message on screen 66 such as "Emergency Service Search ..." in accordance with the method of FIG.

Data interface connection 60 allows software running on computer 58 to be upgraded and / or changed. In this particular embodiment, the computer 58 includes 186 processors.

Emergency call attempts are allowed at any time, including when the cellular phone 50 is locked or when no service is available. If an emergency call attempt is made when no service is available, the cellular phone 50 will continue to run until the call is exhausted (by pressing END) until the search is canceled (by pressing END) until the phone battery runs out (externally). The scan will continue for service until there is no power) or until cellular telephone 50 is turned off.

Only the specific number designated as the true emergency number puts the cellular phone 50 into the emergency call mode in which the method of FIG. 1 is activated. The specific number is edited through the Product Support Tool (PST) or through software hard-coding.

Emergency telephone numbers such as 911 are not global and may vary by country. The wireless carrier can provide a special registration in an electronic directory designating another emergency number. When a user dials a number or code associated with an emergency number in the phone book, emergency call processing is initiated in accordance with the teachings of the present invention. See, eg, " SPECIAL PHONEBOOK ENTRIES ", filed Feb. 9, 1999, filed in US Pat. No. 09 / 246,395, assigned to the assignee of the present invention and used herein for reference. Software for executing the phone book can be run on the computer 58.

For clarity, additional circuits such as clocking circuits and power supplies are not shown in the cellular telephone 50, but those skilled in the art will know where and how to include additional circuits that are essential.

FIG. 4 is a diagram illustrating various states of the display screen 66 of the cellular telephone 50 of FIG. 3 when the cellular telephone 50 is cycled in various states 80 according to the method of FIG. 1.

3 and 4, when the user dials 911, the number 911 is displayed in the first state 82, and the cellular phone 50 enters the emergency call mode. If wireless service is lost and / or wireless service search is essential, display screen 66 enters second state 84 and displays the following message: "Searching for emergency service ...". The message has an animated cycle. In addition, the elapsed time is displayed on display screen 66 to indicate the time elapsed from the initial emergency call attempt.

If the search is in process and the system, i.e., no wireless service, is acquired after one minute, the display screen 66 enters the third state 86 and displays the following status message: "Emergency search continues ...". Status messages reappear every minute of search. The message is displayed for 7 seconds and the backlight feature of the display screen 66 is activated for a 7 second period.

If the wireless service is enabled or obtained, the display screen 66 enters the fourth state 88 and displays the following message: "Call ... Emergency". When acquiring a wireless service, two beep tones are generated by a ringer (not shown) to obtain the maximum effect, and a call originating action (along with an "Emergency nametag") is called from the time of call acquisition. Occurs until the end.

If the user of the cellular telephone 50 issues an emergency call and the emergency number is not stored in the user directory under the user-defined name, the telephone automatically attaches the emergency name tag. In particular, the term "emergency" is displayed to inform the user that an emergency call is occurring.

If cellular telephone 50 acquires an undesirable system for wireless service to make an emergency call, the roaming indicator on display screen 66 is activated and creates a flash for the emergency call. This occurs when the wireless service is not yet valid at the time of the call attempt and non-standard search and acquisition is required to obtain the wireless service.

If silent redialing fails, a beep tone occurs (and may occur through speaker 70); The keypad 64 is back-lit; Then the following message is displayed: "Searching for emergency services ...".

Therefore, if a cellular telephone user attempts an emergency call such as 911 in the United States, the cellular telephone enters a special emergency 911 mode. In the emergency 911 mode, if the telephone 50 cannot connect with the emergency call center via wireless service, the cellular telephone 50 notifies the user that it is searching for emergency services. If cellular telephone 50 obtains the wireless service, it automatically attempts to establish a call, i.e., attempt to make a call. If the call origination is unsuccessful and the cellular phone 50 currently obtains the wireless service, the cellular phone 50 automatically retries the call origination. If the call origination failed and the cellular telephone 50 did not acquire the wireless service, the cellular telephone 50 notifies the user that the wireless service has been lost, and the telephone 50 calls for an emergency call occurrence to be successful or the call signal is lost. The above steps are repeated until terminated by the user or the automatic retry ends.

Thus, the present invention has been described herein with reference to specific embodiments for specific applications. Those skilled in the art having access to the lessons will appreciate additional variations, applications, and embodiments within the scope of the invention.

Therefore, it is intended that the appended claims cover all such applications, modifications, variations and embodiments within the scope of the invention.

Claims (14)

A system for facilitating wireless call connection to an emergency call center, First means for attempting a call to an emergency call center via a wireless service provider; Second means for monitoring the validity of a service provided by the wireless service provider to determine whether the service is valid from the wireless service provider; And And third means for completing the call if the service is determined and valid by the second means. The system of claim 1, wherein the first means comprises a cellular telephone. 2. The system of claim 1, wherein the second means includes software for searching for a wireless service through which an emergency call can be made through the wireless service provider. 2. The method of claim 1, wherein the third means, when the wireless service is determined and valid via the second means, repeatedly dials the telephone number of the emergency call center until the call is completed or established. And software for the system. 5. The system of claim 4, wherein said telephone number is 911. 5. The system of claim 4, wherein the software comprises silent-redialing software. The system of claim 1, wherein the second and third means are executed via software running on a computer included in the first means. 8. The system of claim 7, wherein the computer is in communication with a data interface cable and comprises a 186 processor. A system for facilitating a wireless call connection to an emergency service, First means for attempting a call to an emergency call center via a wireless service provider; Second means for monitoring a service validity provided by the wireless service provider to determine a time period for activating the first means; And And third means for activating said first means in response to said time period provided by said second means. 10. The system of claim 9, further comprising fourth means for selectively stopping the operation of the second and third means in response to a predetermined user input to the first means. 11. The method of claim 10, wherein the time period is such that when the user of the wireless telephone attempts the call via the first means and the user cancels the operation of the first means via the fourth means. And a time period between times. 12. The system of claim 10, wherein said first means is a cellular telephone. 13. The system of claim 12, wherein said second means and said third means comprise silent redial software operating on a computer included in said cellular telephone. A method for facilitating a wireless call connection with an emergency service, First attempting a call to an emergency call center via a wireless service provider; Monitoring wireless service validity to determine if the service is valid from the wireless service provider; And If the service is determined and valid in the monitoring step, completing the call.