Methods and apparatus for in-device coexistence detection and mitigation

• US 9,504,057 B2
• Filed: 09/27/2012
• Issued: 11/22/2016
• Est. Priority Date: 05/11/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Ahmadi, Sassan
• Primary Examiner(s): Nguyen, Hai V
• Application Number:
  US13/629,342
• Publication Number:
  US 20130303214A1
• Time in Patent Office: 1,517 Days
• Field of Search: 455/501
• US Class Current: 1/1
• CPC Class Codes: H04W 72/1215 for collaboration of different radio technologies
• CPC Class Codes: H04W 76/28 Discontinuous transmission [DTX]; Discontinuous reception [DRX]
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

Methods and apparatus for detecting and mitigating interface conditions at a multi-radio device. In one embodiment, a multi-radio device monitors and detects an in-device coexistence (IDC) interference condition which is, for example, caused by concurrent operation of radios. In response, the device notifies a network entity (e.g., a Long Term Evolution (LTE) eNodeB) of the detected IDC condition. Upon receiving the notification of the IDC condition, the network entity may implement or invoke a mitigation scheme in order to reduce the amount of IDC experienced at the client device.

Claims

1. A method for mitigating multi-radio interference at a wireless device operating within a cellular network, the method comprising:

by the wireless device;

obtaining, from a second wireless device proximate to the wireless device via a wireless connection between the wireless device and the second wireless device, information about an interference condition between at least two radio interfaces of the wireless device to occur at a scheduled time;

in response to receipt of the information from the second wireless device, sending in-device coexistence (IDC) Condition Trigger message to the cellular network while in a discontinuous reception (DRX) ON mode;

in response to receipt of an IDC Condition Acknowledge message from the cellular network indicating successful receipt of the IDC Condition Trigger message, operating a first radio interface of the at least two radio interfaces of the wireless device in a DRX OFF mode at the scheduled time to mitigate the interference condition; and

subsequent to the scheduled time, operating the first radio interface of the wireless device in the DRX ON mode.

2. The method of claim 1, wherein the information about the interference condition comprises an indication of a determination of multi-radio interference to occur at the scheduled time at the wireless device.

3. The method of claim 1, wherein the information about the interference condition comprises metrics measured by the second wireless device for the wireless device.

4. The method of claim 1, wherein the first radio interface of the wireless device comprises a Long Term Evolution (LTE) cellular interface, and a second radio interface of the at least two radio interfaces of the wireless device operates in an Industrial Scientific Medical (ISM) frequency band.

5. The method of claim 4, wherein the second radio interface comprises a Wireless Local Area Network (WLAN) compliant interface.

6. The method of claim 1, wherein the wireless connection between the wireless device and the second wireless device comprises a Wi-Fi link or a Personal Area Network (PAN) link.

7. The method of claim 6, wherein proximity of the wireless device to the second wireless device is deemed sufficient for the second wireless device to measure metrics for the wireless device based on establishment of the PAN link.

8. A wireless device, comprising:

a processor;

a first wireless interface and a second wireless interface communicatively coupled to the processor and comprising one or more antennas; and

a memory storing instructions that, when executed by the processor, cause the wireless device to;

obtain, from a second wireless device proximate to the wireless device via a wireless connection between the wireless device and the second wireless device, information about an interference condition between the first wireless interface and the second wireless interface of the wireless device to occur at a scheduled time;

in response to receipt of the information from the second wireless device, send an in-device coexistence (IDC) Condition Trigger message to the cellular network while in a discontinuous reception (DRX) ON mode;

in response to receipt of an DC Condition Acknowledge message from the cellular network indicating successful receipt of the IDC Condition Trigger message, operate the first wireless interface in a DRX OFF mode at the scheduled time to mitigate the interference condition; and

subsequent to the scheduled time, operate the first wireless interface in the DRX ON mode.

9. The wireless device of claim 8, wherein the information about the interference condition comprises an indication of a determination of multi-radio interference to occur at the scheduled time at the wireless device.

10. The wireless device of claim 8, wherein the information about the interference condition comprises metrics measured by the second wireless device for the wireless device.

11. The wireless device of claim 8, wherein the first wireless interface of the wireless device comprises a Long Term Evolution (LTE) cellular wireless interface, and the second wireless interface operates in an Industrial Scientific Medical (ISM) frequency band.

12. The wireless device of claim 8, wherein the wireless connection between the wireless device and the second wireless device comprises a Wi-Fi link or a Personal Area Network (PAN) link.

13. The wireless device of claim 8, wherein proximity of the wireless device to the second wireless device is deemed sufficient for the second wireless device to measure metrics for the wireless device based on establishment of the PAN link.

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

a processor; and

a memory storing instructions that, when executed by the processor, cause the mobile wireless device to;

obtain, from a second wireless device proximate to the mobile wireless device via a wireless connection between the mobile wireless device and the second wireless device, information about an interference condition between wireless interfaces of the mobile wireless device to occur at a scheduled time;

in response to receipt of the information from the second wireless device, send a first message to a cellular network;

in response to receipt of a second message from the cellular network indicating successful receipt of the first message, adjust operation of the wireless interfaces at the scheduled time to mitigate the interference condition; and

subsequent to the scheduled time, readjust operation of the wireless interfaces.

15. The apparatus of claim 14, wherein the wireless connection between the mobile wireless device and the second wireless device comprises a Wi-Fi link or a Personal Area Network (PAN) link.

16. The apparatus of claim 14, wherein the information about the interference condition comprises metrics measured by the second wireless device for the mobile wireless device.

17. The apparatus of claim 14, wherein the mobile wireless device adjusts operation of the wireless interfaces at the scheduled time to mitigate the interference condition by adjusting discontinuous reception (DRX) timers to schedule longer periods of time where the mobile wireless device refrains from monitoring a downlink control channel to reduce activity of one the wireless interfaces.

18. The apparatus of claim 14, wherein the mobile wireless device adjusts operation of the wireless interfaces at the scheduled time to mitigate the interference condition by adjusting gap measurements to cause the mobile wireless device to measure and report neighbor cell search measurements less frequently to reduce activity of one of the wireless interfaces.

19. The apparatus of claim 14, wherein the first message sent to the wireless network comprises an estimation of an activity time for one of the wireless interfaces, and the second message received from the wireless network comprises an adjustment to discontinuous reception (DRX) timers or measurement gap parameters based on the estimation of activity time.

20. The apparatus of claim 19, wherein the estimation of the activity time for one of the wireless interfaces comprises an estimate of ISM-radio transmission intervals for the one of the wireless interfaces.