Operational state mismatch identification for a mobile device

• US 8,885,517 B2
• Filed: 06/13/2012
• Issued: 11/11/2014
• Est. Priority Date: 02/16/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Deivasigamani, Giri Prassad, Nukala, Gaurav, Alam, Muhammad A.
• Primary Examiner(s): Sefcheck, Gregory
• Assistant Examiner(s): MITCHELL, DANIEL D
• Application Number:
  US13/495,686
• Publication Number:
  US 20130215834A1
• Time in Patent Office: 881 Days
• Field of Search: None
• US Class Current: 370/254
• CPC Class Codes: H04W 76/27 Transitions between radio resource control [RRC] states

Abstract

A method is disclosed for determining an operational state mismatch condition between a user equipment (UE) and a network (NW) in a 3^rd generation partnership project long term evolution (3GPP LTE) network. In one embodiment, the UE can monitor messages from the NW. If the messages are not consistent with a current UE operational state, then a state mismatch is determined. In another embodiment, the UE can monitor a paging channel. If the UE receives a paging message that is not consistent with a current UE operational state, then a state mismatch is determined.

Claims

1. A method for recovering from a radio resource control (RRC) operational state mismatch between a user equipment (UE) device and one or more network elements of a network (NW) operating in accordance with a Long Term Evolution (LTE) protocol, the method comprising the UE device:

determining a first RRC operational state of the UE device, wherein the first RRC operational state of the UE device includes an RRC idle state or an RRC connected state;

determining the RRC operational state mismatch when the first RRC operational state of the UE device does not match a first RRC operational state for the UE device maintained at the one or more network elements of the NW, wherein the first RRC operational state for the UE device maintained at the one or more network elements of the NW includes an RRC idle state or an RRC connected state;

sending at least one RRC message from the UE device to the NW to release NW resources assigned to the UE device, in response to determining the RRC operational state mismatch; and

transitioning the UE device from the first RRC operational state of the UE device directly to a second RRC operational state of the UE device after sending the at least one RRC message to the NW, wherein the second RRC operational state of the UE device includes an RRC idle state or an RRC connected state, and

wherein the second RRC operational state of the UE device matches the first RRC operational state for the UE device maintained at the one or more network elements of the NW.

2. The method of claim 1, wherein determining the RRC operational state mismatch further comprises the UE device:

determining a time period during which to receive grant response messages from the NW in response to schedule request messages sent from the UE device to the NW; and

determining the RRC operational state mismatch when no grant response messages are received from the NW during the time period.

3. The method of claim 2, wherein the time period during which to receive grant response messages from the NW corresponds to a connection release time period that is associated with the LTE protocol.

4. The method of claim 1, wherein the first RRC operational state of the UE device comprises the RRC connected state and the second RRC operational state of the UE device comprises the RRC idle state.

5. The method of claim 1, wherein the at least one RRC message comprises at least one RRC connection release message.

6. The method of claim 1, wherein determining the RRC operational state mismatch further comprises the UE device, while in the first RRC operational state of the UE device:

monitoring a paging channel; and

determining the RRC operational state mismatch when at least one page message from the NW is received,

wherein the first RRC operational state of the UE device is the RRC connected state and the second RRC operational state of the UE device is the RRC idle state.

7. The method of claim 6, wherein the at least one page message comprises at least a positive integer number N of page messages received from the NW, and the method further comprises the UE device:

increasing N in response to a worsening of communication channel conditions; and

decreasing N in response to an improving of communication channel conditions.

8. The method of claim 1, wherein the at least one RRC message comprises at least a positive integer number M of RRC messages, and the method further comprises the UE device:

increasing M in response to a degradation of communication channel conditions; and

decreasing M in response to an improvement in communication channel conditions.

9. A non-transitory computer-readable medium storing executable instructions that, when executed by one or more processors of a user equipment (UE) device, causes the UE device to:

determine a first radio resource control (RRC) operating state of the UE device when the UE Device is operating in a Long Term Evolution (LTE) network (NW), wherein the first RRC operating state of the UE device includes an RRC idle state or an RRC connected state;

determine an RRC operating state mismatch condition between the UE device and the LTE NW when the first RRC operating state of the UE device and a first RRC operating state for the UE device maintained at the LTE NW do not match, wherein the first RRC operating state for the UE device maintained at the LTE NW includes an RRC idle state or an RRC connected state;

send at least one RRC message to the LTE NW in response to the determined RRC operating state mismatch condition; and

transition the UE device from the first RRC operating state of the UE device directly to a second RRC operating state of the UE device that corresponds to the first RRC operating state for the UE device maintained at the LTE NW after sending the at least one RRC message to the LTE NW, wherein the second RRC operating state of the UE device includes an RRC idle state or an RRC connected state.

10. The non-transitory computer-readable medium of claim 9, wherein the UE device determines the RRC operating state mismatch condition by:

determining a first time period during which to receive grant response messages from the LTE NW; and

determining that the first RRC operating state of the UE device does not match the first RRC operating state for the UE device maintained at the LTE NW when no grant response messages are received from the LTE NW during the determined first time period.

11. The non-transitory computer-readable medium of claim 9, wherein the UE device determines the RRC operating state mismatch condition by:

monitoring a paging channel; and

determining that the first RRC operating state of the UE device does not match the first RRC operating state for the UE device maintained at the LTE NW when at least one paging message is received on the paging channel.

12. The non-transitory computer-readable medium of claim 11, wherein the at least one paging message comprises at least a positive integer number N of paging messages, and the execution of the executable instructions by the one or more processors, further causes the UE device to:

increase N in response to a degradation of communication channel conditions; and

decrease N in response to an improvement in communication channel conditions.

13. The non-transitory computer-readable medium of claim 9, wherein the UE device sends the at least one RRC message to the LTE NW by sending a RRC connection release message to the LTE NW.

14. The non-transitory computer-readable medium of claim 9, wherein the UE device sends the at least one RRC message to the LTE NW by sending a radio link failure (RLF) message to the LTE NW.

15. The non-transitory computer-readable medium of claim 9, wherein the at least one RRC message comprises at least a positive integer M of messages, and the execution of the executable instructions by the one or more processors, further causes the UE device to:

increase M in response to a degradation of communication channel conditions; and

decrease M in response to an improvement in communication channel conditions.

16. An apparatus for recovering from a radio resource control (RRC) operational state mismatch between a user equipment (UE) device and one or more network elements of a network (NW), the apparatus comprising:

one or more processors;

a memory coupled with the one or more processors and storing executable instructions; and

at least one wireless transceiver coupled with the one or more processors and the memory,

wherein an execution of the executable instructions by the one or more processors, causes the apparatus to;

determine a first RRC operational state of the UE device, wherein the first RRC operational state of the UE device includes an RRC idle state or an RRC connected state;

determine an RRC operational state mismatch when the first RRC operational state of the UE device does not match a first RRC operational state for the UE device maintained at the NW, wherein the first RRC operational state for the UE device maintained at the NW includes an RRC idle state or an RRC connected state;

send at least one RRC message from the UE device to the NW to release NW resources assigned to the UE device, in response to determining the RRC operational state mismatch; and

transition the UE device from the first RRC operational state of the UE device directly to a second RRC operational state of the UE device after sending the at least one RRC message to the NW, wherein the second RRC operational state of the UE device includes an RRC idle state or an RRC connected state, and

wherein the second RRC operational state of the UE device matches the first RRC operational state associated with the UE device of the NW.

17. The apparatus of claim 16, wherein the apparatus determines the RRC operational state mismatch by:

determining a time period to receive grant response messages from the NW in response to schedule request messages sent from the UE device to the NW; and

determining the RRC operational state mismatch when no grant response messages are received from the NW during the time period.

18. The apparatus of claim 16, wherein the apparatus determines the RRC operational state mismatch by:

monitoring a paging channel; and

determining that the first RRC operational state of the UE device does not match the first RRC operational state for the UE device maintained at the NW when at least one paging message is received from the NW on the paging channel.

19. The apparatus of claim 18, wherein the at least one paging message comprises at least a positive integer number N of paging messages, and the execution of the executable instructions by the one or more processors, further causes the apparatus to:

increase N in response to a degradation of communication channel conditions; and

decrease N in response to an improvement in communication channel conditions.