Guard timer to optimize E911 call handling

• US 10,084,914 B1
• Filed: 07/31/2017
• Issued: 09/25/2018
• Est. Priority Date: 03/24/2017
• Status: Active Grant

• Current Assignee: T-Mobile USA, Inc. (Deutsche Telekom AG)
• Original Assignee: T-Mobile USA, Inc. (Deutsche Telekom AG)
• Inventors: Chiang, Hsin-Fu Henry, Nimbavikar, Gunjan
• Primary Examiner(s): Woo, Stella
• Application Number:
  US15/665,272
• Publication Number:
  US 20180278747A1
• Time in Patent Office: 421 Days
• Field of Search: 379 37, 379 38, 379 45, 37921501, 45540401, 45540402
• CPC Class Codes: H04M 1/6505 storing speech in digital form
• CPC Class Codes: H04M 1/72418 for supporting emergency services
• CPC Class Codes: H04M 1/72513 On hold, intercom or transfer communication modes
• CPC Class Codes: H04M 11/04 with alarm systems, e.g. fire, police or burglar alarm systems
• CPC Class Codes: H04M 11/045 using recorded signals, e.g. speech
• CPC Class Codes: H04M 2201/14 Delay circuits; Timers
• CPC Class Codes: H04M 2203/2005 Temporarily overriding a service configuration
• CPC Class Codes: H04M 3/42059 Making use of the calling party identifier
• CPC Class Codes: H04M 3/4288 Notifying a called subscriber of an incoming call during an ongoing call, e.g. Call Waiting
• CPC Class Codes: H04M 3/5116 for emergency applications
• CPC Class Codes: H04M 3/533 Voice mail systems
• CPC Class Codes: H04M 7/0078 Security; Fraud detection; Fraud prevention
• CPC Class Codes: H04M 7/0084 Network monitoring; Error detection; Error recovery; Network testing
• CPC Class Codes: H04W 4/16 Communication-related supplementary services, e.g. call-transfer or call-hold
• CPC Class Codes: H04W 4/90 Services for handling of emergency or hazardous situations, e.g. earthquake and tsunami warning systems [ETWS]
• CPC Class Codes: H04W 76/38 triggered by timers

Abstract

Systems and methods for optimized call handling during e911 calls. Normally, when a user equipment (UE) is connected to a public safety answering point (PSAP)—e.g., is on a 911 call—all incoming calls are automatically routed to voicemail. In contrast, the systems and methods disclosed herein enable calls that were dialed within a predetermined time window of the 911 call to be sent through to call-waiting to enable the user to accept or reject the call. The system can use a “guard timer” to determine whether a call is within the predetermined time window. The system can include a single guard timer for all incoming calls—e.g., “any call made from the UE within the previous X minutes prior to the 911 call.” The system can also include individual guard timers for each call that expire separately relative to the call'"'"'s proximity to the 911 call.

Claims

1. A method comprising:

determining, by a processor of a user'"'"'s UE, that a transceiver on a user'"'"'s UE is connected to a public safety answering point (PSAP);

while the user'"'"'s UE is connected to the PSAP,

receiving, at the transceiver of the user'"'"'s UE, an incoming call from a caller'"'"'s UE;

determining, by the processor, whether a number associated with the caller'"'"'s UE was dialed from the transceiver of the user'"'"'s UE within a predetermined time window of the connection to the PSAP; and

either;

activating, by the processor, call-waiting on the user'"'"'s UE for the incoming call if the caller'"'"'s UE was previously dialed from the transceiver of the user'"'"'s UE within the predetermined time window of the connection to the PSAP;

or

sending, by the processor or the transceiver, the incoming call directly to voicemail if the caller'"'"'s UE was not previously dialed from the transceiver of the user'"'"'s UE within the predetermined time window of the connection to the PSAP.

2. The method of claim 1, wherein the predetermined time window comprises all calls made from the user'"'"'s UE in a five-minute window prior to connecting to the PSAP.

3. The method of claim 1, further comprising:

determining, by the processor, whether a number associated with the caller'"'"'s UE is included in a list of numbers associated with one or more PSAPs;

activating, by the processor, call-waiting on the user'"'"'s UE for the incoming call if the caller'"'"'s UE is included in a list of numbers associated with one or more PSAPs; and

sending, by the processor or the transceiver, the incoming call directly to voicemail if the caller'"'"'s UE is not included in a list of numbers associated with one or more PSAPs.

4. The method of claim 1, wherein determining that the incoming call was not dialed from the transceiver of the user'"'"'s UE within the predetermined time window of the connection to the PSAP comprises determining that the incoming call is not included in a call history of the user'"'"'s UE.

5. The method of claim 1, wherein determining that the incoming call was not dialed from the transceiver of the user'"'"'s UE within the predetermined time window of the connection to the PSAP comprises determining that the incoming call is included in a call history of the user'"'"'s UE, but outside the predetermined time window.

6. The method of claim 5, wherein the predetermined time window comprises all calls made from the user'"'"'s UE in a ten-minute window prior to connecting to the PSAP.

7. The method of claim 1, wherein determining that the transceiver on the user'"'"'s UE is connected to a PSAP comprises receiving, by the processor, a signal from a dialer on the user'"'"'s UE that a user has dialed 911.

8. A method comprising:

while a user'"'"'s UE is connected to a public safety answering point (PSAP),

receiving, at a transceiver of a network entity associated with a telecommunications network, an incoming call for the user'"'"'s UE from a caller'"'"'s UE;

determining, by a processor of the network entity, that the user'"'"'s UE is connected to the PSAP;

determining, by the processor, whether a number associated with the caller'"'"'s UE was dialed from the transceiver of the user'"'"'s UE within a predetermined time window of the connection to the PSAP; and

sending, by the transceiver of the network entity, the incoming call to a transceiver of the user'"'"'s UE in response to determining that the number associated with the caller'"'"'s UE was dialed from the transceiver of the user'"'"'s UE within a predetermined time window of the connection to the PSAP.

9. The method of claim 8, wherein sending, by the transceiver of the network entity, the incoming call to the transceiver of the user'"'"'s UE activates call-waiting on the user'"'"'s UE to enable the incoming call to be accepted or rejected on the user'"'"'s UE.

10. The method of claim 8, wherein the predetermined time window comprises all calls made from the user'"'"'s UE in a two-minute window prior to connecting to the PSAP.

11. The method of claim 8, wherein determining that the incoming call was not previously dialed from the transceiver of the user'"'"'s UE within a predetermined time window of the connection to the PSAP comprises determining that the incoming call is from a caller that is not in a call history of the user'"'"'s UE.

12. The method of claim 8, wherein determining, by the processor of the network entity, that the user'"'"'s UE is currently connected to the PSAP comprises receiving a session initiation protocol (SIP) message from the user'"'"'s UE at the network entity including a response code indicating the user is engaged in a 911 call.

13. The method of claim 8, wherein the network entity comprises a telephony application server (TAS).

14. The method of claim 8, wherein the network entity comprises a mobile switching center (MSC).

15. The method of claim 8, further comprising:

determining, by a processor of the network entity, that the user'"'"'s UE has disconnected from the PSAP within three rings of the network entity receiving the incoming call; and

sending, with the transceiver of the network entity, the incoming call to the transceiver of the user'"'"'s UE.

16. A user'"'"'s UE comprising:

a processor;

a transceiver; and

programming instructions that, when executed by the processor, cause the user'"'"'s UE to perform operations including;

determining that the transceiver is connected to a public safety answering point (PSAP);

while the transceiver is connected to the PSAP,

receiving an indication of an incoming call from a caller'"'"'s UE;

determining whether a number associated with the caller'"'"'s UE was dialed from the transceiver of the user'"'"'s UE within a predetermined time window of the connection to the PSAP; and

either;

activating call-waiting on the user'"'"'s UE for the incoming call if the caller'"'"'s UE was previously dialed from the transceiver of the user'"'"'s UE within the predetermined time window of the connection to the PSAP, or

sending the incoming call directly to voicemail if the caller'"'"'s UE was not previously dialed from the transceiver of the user'"'"'s UE within the predetermined time window of the connection to the PSAP.

17. The user'"'"'s UE of claim 16, wherein the predetermined time window is 180 seconds.

18. The user'"'"'s UE of claim 16, wherein the predetermined amount of time window is five minutes.

19. The user'"'"'s UE of claim 16, wherein determining that the transceiver on the user'"'"'s UE is connected to the PSAP comprises receiving, at the processor, a signal from a dialer on the user'"'"'s UE that a user has dialed 911.

20. The user'"'"'s UE of claim 16, wherein the operations further include:

determining whether a number associated with the caller'"'"'s UE is included in a list of numbers associated with one or more PSAPs;

activating call-waiting on the user'"'"'s UE for the incoming call if the caller'"'"'s UE is included in a list of numbers associated with one or more PSAPs; and

sending the incoming call directly to voicemail if the caller'"'"'s UE is not included in a list of numbers associated with one or more PSAPs.