Determining connection states of a mobile wireless device

• US 10,306,495 B2
• Filed: 01/30/2017
• Issued: 05/28/2019
• Est. Priority Date: 06/29/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Su, Li, Nimmala, Srinivasan
• Primary Examiner(s): Heiber, Shantell L
• Application Number:
  US15/419,868
• Publication Number:
  US 20170303149A1
• Time in Patent Office: 848 Days
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 76/19 Connection re-establishment
• CPC Class Codes: H04W 76/27 Transitions between radio resource control [RRC] states

Abstract

Methods, apparatuses and computer readable media are described that determine a connection state between a mobile wireless device and a wireless network upon detection of an interruption of a connection between the mobile wireless device and the wireless network. The mobile wireless device transmits an uplink resource allocation message to the wireless network, and when receiving no response to the uplink resource allocation message, transmits a random access message to the wireless network. When receiving no response from the wireless network to the random access message, the mobile wireless device executes a radio link failure procedure. In an embodiment, the uplink resource allocation message includes a unique identifier for an existing radio resource control connection between the mobile wireless device and the wireless network.

Claims

1. A method comprising:

by a mobile wireless device;

in response to determining a time duration of an interruption of a connection with a wireless network exceeds a timeout threshold;

transmitting, while in a Radio Resource Control (RRC) connected state, at least one scheduling request (SR) message to the wireless network to determine whether an RRC connection between the mobile wireless device and the wireless network is active;

when receiving no response from the wireless network to the at least one SR message, transmitting, while in the RRC connected state, at least one random access message to the wireless network; and

when receiving no response from the wireless network to the at least one random access message, releasing internally the RRC connection to the wireless network by at least updating an internal state of the mobile wireless device from the RRC connected state to an RRC idle state,

wherein the mobile wireless device transmits the at least SR message irrespective of whether transmit buffers in the mobile wireless device include pending uplink data.

2. The method of claim 1, further comprising:

by the mobile wireless device;

subsequent to releasing internally the RRC connection to the wireless network, establishing a new RRC connection to the wireless network.

3. The method of claim 1, further comprising:

by the mobile wireless device;

subsequent to releasing internally the RRC connection to the wireless network, sending an RRC re-establishment request message to the wireless network to re-establish the RRC connection.

4. The method of claim 1, further comprising:

by the mobile wireless device;

when receiving a response from the wireless network to the at least one SR message, sending a buffer status report (BSR) to the wireless network.

5. The method of claim 4, wherein the BSR comprises an indication of an empty uplink transmit buffer in the mobile wireless device.

6. The method of claim 1, wherein the at least one SR message comprises N>

2 SR messages, where N is less than a maximum number of repetitions for consecutive SR messages configured by the wireless network.

7. The method of claim 1, further comprising:

by the mobile wireless device;

when receiving a response from the wireless network to the at least one random access message, sending a buffer status report (BSR) to the wireless network.

8. The method of claim 1, further comprising:

by the mobile wireless device;

when receiving no response from the wireless network to the at least one random access message, executing a radio link failure procedure.

9. The method of claim 1, wherein the at least one random access message comprises a message that includes a unique identifier for the RRC connection between the mobile wireless device and the wireless network.

10. The method of claim 1, wherein the at least one random access message comprises M>

2 preamble messages, where M is less than a maximum number of consecutive preamble repetitions configured by the wireless network.

11. The method of claim 1, wherein the interruption of the connection comprises a tune-away event for the mobile wireless device to communicate with another wireless network.

12. A mobile wireless device comprising:

wireless circuitry configurable for communication with a first wireless network and a second wireless network; and

at least one processor communicatively coupled to the wireless circuitry and to a memory storing instructions that, when executed by the at least one processor, cause the mobile wireless device to;

in response to determining a time duration of an interruption of a connection with the first wireless network exceeds a timeout threshold;

transmit, while in a Radio Resource Control (RRC) connected state, at least one scheduling request (SR) message to the first wireless network to determine whether an RRC connection between the mobile wireless device and the first wireless network is active;

when receiving no response from the first wireless network to the at least one SR message, transmit, while in the RRC connected state, at least one random access message to the first wireless network; and

when receiving no response from the first wireless network to the at least one random access message, release internally the RRC connection to the first wireless network by at least updating an internal state of the mobile wireless device from the RRC connected state to an RRC idle state,

wherein the mobile wireless device transmits the at least SR message irrespective of whether transmit buffers in the mobile wireless device include pending uplink data.

13. The mobile wireless device of claim 12, wherein execution of the instructions further causes the mobile wireless device to:

when receiving a response from the first wireless network to the at least one SR message, send a buffer status report (BSR) to the first wireless network.

14. The mobile wireless device of claim 12, wherein the interruption of the connection to the first wireless network comprises a tune-away event for the mobile wireless device to communicate with the second wireless network.

15. The mobile wireless device of claim 12, wherein the at least one SR message comprises N>

2 SR messages, where N is less than a maximum number of repetitions for consecutive SR messages configured by the first wireless network.

16. The mobile wireless device of claim 12, wherein execution of the instructions further causes the mobile wireless device to:

when receiving no response from the first wireless network to the at least one random access message, execute a radio link failure procedure.

17. An apparatus configurable for operation in a mobile wireless device, the apparatus comprising:

at least one processor; and

a memory communicatively coupled to the at least one processor and storing instructions that, when executed by the at least one processor, cause the mobile wireless device to;

in response to determining a time duration of an interruption of a connection with a wireless network exceeds a timeout threshold;

transmit, while in a Radio Resource Control (RRC) connected state, at least one scheduling request (SR) message to the wireless network to determine whether an RRC connection between the mobile wireless device and the wireless network is active;

when receiving no response from the wireless network to the at least one SR message, transmit, while in the RRC connected state, at least one random access message to the wireless network; and

when receiving no response from the wireless network to the at least one random access message, release internally the RRC connection to the first wireless network by at least updating an internal state of the mobile wireless device from the RRC connected state to an RRC idle state,

wherein the mobile wireless device transmits the at least SR message irrespective of whether transmit buffers in the mobile wireless device include pending uplink data.

18. The apparatus of claim 17, wherein the at least one SR message comprises N>

2 SR messages, where N is less than a maximum number of repetitions for consecutive SR messages configured by the wireless network.

19. The apparatus of claim 17, wherein execution of the instructions further causes the mobile wireless device to:

when receiving no response from the wireless network to the at least one random access message, execute a radio link failure procedure.