Decreasing RSSI settling time in low-power mode systems

• US 9,253,674 B2
• Filed: 07/26/2011
• Issued: 02/02/2016
• Est. Priority Date: 07/26/2011
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Plantronics, Inc.
• Inventors: Rosener, Doug
• Primary Examiner(s): HUANG, WEN WU
• Application Number:
  US13/191,248
• Publication Number:
  US 20130029607A1
• Time in Patent Office: 1,652 Days
• Field of Search: 455/456.1, 455/6, 455/457, 455/404.2
• US Class Current: 1/1
• CPC Class Codes: H04M 1/6066 including a wireless connection
• CPC Class Codes: H04M 2250/02 including a Bluetooth interface
• CPC Class Codes: H04M 2250/06 including a wireless LAN interface
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 52/0245 according to signal strength
• CPC Class Codes: H04W 64/006 with additional information processing, e.g. for direction or speed determination
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Methods and apparatuses presented herein advantageously enable more accurate RSSI measurements by waking up a mobile device from a low-power mode in certain pre-designated situations. These situations include detecting certain trends in RSSI values, detecting changes in transmit power, or detecting motion. The trigger which causes the mobile device to enter the active mode from the low power mode may differ in varying examples.

Claims

1. A method for measuring RSSI comprising:

receiving a first plurality of RSSI values at a first rate during operation of a mobile device in a reduced power mode;

processing the first plurality of RSSI values to identify a current movement of the mobile device with respect to a base unit during the reduced power mode, wherein the processing comprises identifying a trend in the first plurality of RSSI values;

entering an active mode at the mobile device responsive to identification of the current movement of the mobile device with respect to the base unit, the active mode comprising receiving a plurality of RSSI values at a second rate higher than the first rate;

receiving a second plurality of RSSI values at the second rate during operation of the mobile device in the active mode; and

processing the second plurality of RSSI values to determine a range of the mobile device with respect to the base unit.

2. The method of claim 1, wherein processing the second plurality of RSSI values comprises determining an average RSSI value across a predetermined number of most recently received RSSI values.

3. The method of claim 1, further comprising returning to the reduced power mode at the mobile device following processing the second plurality of RSSI values to determine the range of the mobile device with respect to the base unit.

4. The method of claim 3, wherein returning to the reduced power mode at the mobile device is responsive to receiving a reduced power mode command message at the mobile device from a base unit.

5. The method of claim 1, wherein processing the second plurality of RSSI values further comprises identifying a stationary trend or no trend in the second plurality of RSSI values indicating lack of movement of the mobile device with respect to the base unit, wherein the mobile device returns to the reduced power mode responsive to identifying the stationary trend or no trend.

6. The method of claim 1, wherein the trend in the first plurality of RSSI values indicating possible movement of the mobile device comprises a predetermined number of increasing RSSI values or a predetermined number of decreasing RSSI values.

7. The method of claim 1, wherein the trend in the first plurality of RSSI values indicating possible movement of the mobile device comprises a predetermined number of increasing RSSI values without repeat or a predetermined number of decreasing RSSI values without repeat.

8. The method of claim 1, wherein the first plurality of RSSI values comprise a first series of RSSI values measured at a first frequency rate associated with the reduced power mode, and the second plurality of RSSI values comprise a second series of RSSI values measured at a second frequency rate associated with the active mode, where the second frequency rate is greater than the first frequency rate.

9. The method of claim 1, wherein entering an active mode at the mobile device is responsive to receiving an enter active mode command message at the mobile device from a base unit.

10. The method of claim 1, wherein the range comprises a near status or a far status.

11. The method of claim 1, wherein the range comprises whether the mobile device is moving or a distance between the mobile device with respect to the base unit.

12. A method comprising:

operating a mobile device in a reduced power mode;

determining a first range of the mobile device with respect to a base unit while operating in the reduced power mode;

receiving a status update message during operation of a mobile device in a reduced power mode, wherein the status update message comprises a detection of movement of the mobile device utilizing a motion detector;

entering an active mode at the mobile device responsive to the status update message comprising the detection of movement of the mobile device utilizing a motion detector;

receiving a plurality of RSSI values during operation of the mobile device in the active mode;

processing the plurality of RSSI values to determine a second range of the mobile device with respect to the base unit; and

returning to the reduced power mode at the mobile device following determining the mobile device is stationary in range with respect to the base unit.

13. The method of claim 12, wherein the status update message further comprises a change in transmit power between a base unit and the mobile device.

14. The method of claim 12, wherein the motion detector is a motion detector external to the mobile device.

15. The method of claim 14, wherein the motion detector external to the mobile device is an infrared detector.

16. The method of claim 12, wherein the motion detector is a motion detector internal to the mobile device.

17. The method of claim 16, wherein the motion detector internal to the mobile device is an accelerometer or gyroscope.

18. The method of claim 12, wherein the status update message further comprises an identified trend in RSSI values.

19. A mobile device comprising:

a wireless transceiver for sending and receiving signals;

a memory storing an operational mode application program for selecting and operating the mobile device in a reduced power mode or an active mode; and

a processor configured to execute the operational mode application program to process a first plurality of RSSI values at a first rate received during the reduced power mode to identify a current movement of the mobile device with respect to a base unit during the reduced power mode, wherein the processing comprises identifying a trend, and switch to the active mode responsive to identifying the current movement of the mobile device, the active mode comprising receiving a plurality of RSSI values at a second rate higher than the first rate, wherein the processor is further configured to process the second plurality of RSSI values received during the active mode at the second rate to determine a range of the mobile device with respect to the base unit.

20. The mobile device of claim 19, wherein the second plurality of RSSI values is processed to determine an average RSSI value across a predetermined number of most recently received RSSI values.

21. The mobile device of claim 19, wherein the operational mode application program is configured to return the mobile device to the reduced power mode at the mobile device following processing the second plurality of RSSI values to determine the range of the mobile device with respect to the base unit.

22. The mobile device of claim 19, wherein the trend in the first plurality of RSSI values indicating possible movement of the mobile device comprises a predetermined number of increasing RSSI values or a predetermined number of decreasing RSSI values.

23. A mobile device comprising:

a wireless transceiver for sending and receiving signals;

a memory storing an operational mode application program for selecting and operating the mobile device in a reduced power mode or an active mode; and

a processor configured to execute the operational mode application program to determine a first range of the mobile device with respect to a base unit while operating the mobile device in the reduced power mode and receive a status update message during the reduced power mode, wherein the status update message comprises a detection of movement of the mobile device utilizing a motion detector, and switch to the active mode responsive to the status update message comprising the detection of movement of the mobile device utilizing a motion detector, wherein the processor is further configured to process a second plurality of RSSI signals received during the active mode to determine a second range of the mobile device with respect to the base unit and switch back to the reduced power mode following a determination the mobile device is stationary in range with respect to the base unit.

24. The mobile device of claim 23, wherein the status update message further comprises a change in transmit power between a base unit and the mobile device.

25. The mobile device of claim 23, wherein the motion detector is a motion detector external to the mobile device.

26. The mobile device of claim 23, wherein the motion detector is a motion detector internal to the mobile device.

27. The mobile device of claim 23, wherein the status update message further comprises an identified trend in RSSI values measured during reduced power mode.