Positioning measurement management

• US 20150271764A1
• Filed: 03/21/2014
• Published: 09/24/2015
• Est. Priority Date: 03/21/2014
• Status: Active Application

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: AGRAWAL, Meghna, DUA, Praveen
• Application Number:
  US14/222,493
• Publication Number:
  US 20150271764A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04W 52/143 Downlink power control
• CPC Class Codes: H04W 52/223 predicting future states of the transmission
• CPC Class Codes: H04W 52/242 taking into account path loss
• CPC Class Codes: H04W 52/246 where the output power of a terminal is based on a path parameter calculated in said terminal
• CPC Class Codes: H04W 52/283 Power depending on the position of the mobile

Abstract

Techniques for controlling transmit (Tx) power of an access point (AP) in a wireless communication system are described herein. An example of a method described herein includes detecting that a positioning exchange between an AP and a mobile device has been initialized; determining an estimated coverage area of the mobile device, an estimated Tx power level of the mobile device, and/or other operating parameters of the mobile device; and controlling a power level used by the AP for transmissions to the mobile device during the positioning exchange based on the determined operating parameters of the mobile device.

Claims

1. A method for controlling transmit (Tx) power of an access point (AP) in a wireless communication system, the method comprising:

detecting initialization of a positioning exchange between the AP and a mobile device;

determining estimated operating parameters of the mobile device, the estimated operating parameters of the mobile device comprising an estimated coverage area of the mobile device and an estimated Tx power level of the mobile device; and

setting an AP Tx power level for transmissions from the AP to the mobile device during the positioning exchange as a function of the estimated operating parameters of the mobile device.

2. The method of claim 1 wherein determining the estimated operating parameters of the mobile device comprises determining the estimated coverage area of the mobile device based at least in part on an estimated position of the mobile device and an estimated communication range of the mobile device.

3. The method of claim 2 wherein setting the AP Tx power level comprises setting the AP Tx power level such that the estimated coverage area of the mobile device is a subset of a coverage area of the AP as defined with respect to the AP Tx power level.

4. The method of claim 1 wherein determining the estimated operating parameters of the mobile device comprises determining the estimated Tx power level of the mobile device based on measured Tx power levels associated with one or more past transmissions from the mobile device.

5. The method of claim 1 wherein determining the estimated operating parameters of the mobile device comprises determining the estimated Tx power level of the mobile device based on information received from the mobile device.

6. The method of claim 1 wherein setting the AP Tx power level comprises setting the AP Tx power level such that a difference between the AP Tx power level and the estimated Tx power level of the mobile device is less than a threshold.

7. The method of claim 1 wherein determining the estimated operating parameters of the mobile device comprises determining at least one of an estimated detection threshold of the mobile device or an estimated path loss between the AP and the mobile device.

8. The method of claim 7 wherein determining the estimated operating parameters of the mobile device further comprises determining the estimated path loss between the AP and the mobile device based on a previous position estimate for the mobile device.

9. The method of claim 7 wherein setting the AP Tx power level comprises:

computing a detectable AP Tx power level for the mobile device based on the estimated detection threshold of the mobile device and the estimated path loss between the AP and the mobile device; and

setting the AP Tx power level as a function of the detectable AP Tx power level for the mobile device.

10. The method of claim 1 further comprising:

receiving, at the AP, information relating to the Tx power level of the mobile device; and

adjusting, at the AP, the AP Tx power level based on the Tx power level of the mobile device.

11. The method of claim 1 further comprising:

transmitting, at the AP, a positioning packet to the mobile device at the AP Tx power level;

attempting, at the AP, to detect an acknowledgment (ACK) from the mobile device for the positioning packet; and

increasing the AP Tx power if the ACK is not detected at the AP.

12. The method of claim 1 wherein:

determining the estimated operating parameters of the mobile device further comprises determining an estimated detection threshold of the mobile device; and

setting the AP Tx power level further comprises setting the AP Tx power level based at least in part on the estimated detection threshold of the mobile device.

13. An apparatus for managing access point (AP) transmission power, the apparatus comprising:

an access point (AP) coordination module configured to detect initialization of a positioning exchange between an AP and a mobile device; and

a network based positioning (NBP) module configured to determine estimated operating parameters of the mobile device, the estimated operating parameters comprising an estimated coverage area of the mobile device and an estimated transmit (Tx) power level of the mobile device, and to set an AP Tx power level for transmissions from the AP to the mobile device during the positioning exchange as a function of the estimated operating parameters of the mobile device.

14. The apparatus of claim 13 wherein the NBP module is further configured to determine the estimated coverage area of the mobile device based at least in part on an estimated position of the mobile device and an estimated communication range of the mobile device.

15. The apparatus of claim 14 wherein the NBP module is further configured to set the AP Tx power level such that the estimated coverage area of the mobile device is a subset of a coverage area of the AP as defined with respect to the AP Tx power level.

16. The apparatus of claim 13 further comprising a mobile history database communicatively coupled to the NBP module and configured to store data relating to one or more past transmissions from the mobile device, wherein the NBP module is further configured to determine the estimated Tx power level of the mobile device based on data stored at the mobile history database.

17. The apparatus of claim 13 further comprising a crowdsourcing module communicatively coupled to the NBP module and configured to obtain, from the mobile device, information relating to the estimated operating parameters of the mobile device, wherein the NBP module is further configured to determine the estimated Tx power level of the mobile device based on the information obtained by the crowdsourcing module.

18. The apparatus of claim 14 wherein the NBP module is further configured to set the AP Tx power level such that a difference between the AP Tx power level and the estimated Tx power level of the mobile device is less than a threshold.

19. The apparatus of claim 13 wherein the NBP module is further configured to determine an estimated detection threshold of the mobile device and an estimated path loss between the AP and the mobile device, to compute a detectable AP Tx power level for the mobile device based on the estimated detection threshold of the mobile device and the estimated path loss between the AP and the mobile device, and to set the AP Tx power level as a function of the detectable AP Tx power level for the mobile device.

20. The apparatus of claim 13 further comprising:

at least one processor configured to perform one or more functions of the AP coordination module and the NBP module; and

a memory coupled to the at least one processor and configured to store data.

21. An apparatus for controlling transmit (Tx) power of an access point (AP) in a wireless communication system, the apparatus comprising:

means for detecting initialization of a positioning exchange between the AP and a mobile device;

means for determining estimated operating parameters of the mobile device, the estimated operating parameters comprising an estimated coverage area of the mobile device and an estimated Tx power level of the mobile device; and

means for setting an AP Tx power level for transmissions from the AP to the mobile device during the positioning exchange as a function of the estimated operating parameters of the mobile device.

22. The apparatus of claim 21 wherein:

the means for determining the estimated operating parameters of the mobile device comprises means for determining the estimated coverage area of the mobile device based at least in part on an estimated position of the mobile device and an estimated communication range of the mobile device; and

the means for setting the AP Tx power level comprises means for setting the AP Tx power level such that the estimated coverage area of the mobile device is a subset of a coverage area of the AP as defined with respect to the AP Tx power level.

23. The apparatus of claim 21 wherein the means for determining the estimated operating parameters of the mobile device comprises determining the estimated Tx power level of the mobile device based on at least one of Tx power levels associated with one or more past transmissions from the mobile device or information collected from the mobile device.

24. The apparatus of claim 21 wherein the means for setting the AP Tx power level comprises means for setting the AP Tx power level such that a difference between the AP Tx power level and the estimated Tx power level of the mobile device is less than a threshold.

25. The apparatus of claim 21 wherein:

the means for determining the estimated operating parameters of the mobile device comprises means for determining an estimated detection threshold of the mobile device and an estimated path loss between the AP and the mobile device; and

the means for setting the AP Tx power level comprises means for computing a detectable AP Tx power level for the mobile device based on the estimated detection threshold of the mobile device and the estimated path loss between the AP and the mobile device and means for setting the AP Tx power level as a function of the detectable AP Tx power level for the mobile device.

26. A non-transitory processor-readable storage medium comprising processor-executable instructions configured to cause a processor to:

detect initialization of a positioning exchange between an access point (AP) and a mobile device;

determine estimated operating parameters of the mobile device, the estimated operating parameters comprising an estimated coverage area of the mobile device and an estimated transmit (Tx) power level of the mobile device; and

set an AP Tx power level for transmissions from the AP to the mobile device during the positioning exchange as a function of the estimated operating parameters of the mobile device.

27. The processor-readable storage medium of claim 26 further comprising instructions configured to cause the processor to:

determine the estimated coverage area of the mobile device based at least in part on an estimated position of the mobile device and an estimated communication range of the mobile device; and

set the AP Tx power level such that the estimated coverage area of the mobile device is a subset of a coverage area of the AP as defined with respect to the AP Tx power level.

28. The processor-readable storage medium of claim 26 further comprising instructions configured to cause the processor to determine the estimated Tx power level of the mobile device based on at least one of Tx power levels associated with one or more past transmissions from the mobile device or information collected from the mobile device.

29. The processor-readable storage medium of claim 26 further comprising instructions configured to cause the processor to set the AP Tx power level such that a difference between the AP Tx power level and the estimated Tx power level of the mobile device is less than a threshold.

30. The processor-readable storage medium of claim 26 further comprising instructions configured to cause the processor to:

determine an estimated detection threshold of the mobile device and an estimated path loss between the AP and the mobile device; and

compute a detectable AP Tx power level for the mobile device based on the estimated detection threshold of the mobile device and the estimated path loss between the AP and the mobile device and setting the AP Tx power level as a function of the detectable AP Tx power level for the mobile device.