Mobile device positioning

• US 8,954,267 B2
• Filed: 02/21/2013
• Issued: 02/10/2015
• Est. Priority Date: 02/21/2013
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Khorashadi, Behrooz, Das, Saumitra Mohan, Chao, Hui
• Primary Examiner(s): CAMBY, RICHARD M
• Application Number:
  US13/773,309
• Publication Number:
  US 20140236476A1
• Time in Patent Office: 719 Days
• Field of Search: 701/445, 701/446, 701/447, 701/450, 701/451, 701/454, 701/409, 455/456.1, 455/456.6, 455/456.5, 455/404.2, 370/328, 370/352
• US Class Current: 701/445
• CPC Class Codes: G01C 21/206 specially adapted for indoor navigation
• CPC Class Codes: G01S 19/42 Determining position
• CPC Class Codes: G01S 5/02521 using a radio-map
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/029 Location-based management or tracking services
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

Methods, apparatus, and computer program products for determining a mobile device location. An example of a method for determining a mobile device location includes receiving signals from a transmitter, measuring signal characteristics of the received signals, and downloading data from a database corresponding to a defined region associated with the transmitters. The downloaded data includes a set of position points, a classification of each position point, and expected signal characteristics for each position point. The method further includes comparing the measured signal characteristics with the expected signal characteristics for each position point, assigning a weight to position points based on the compared signal characteristics, and determining the mobile device location by selecting one position point from the set as a position point solution corresponding to the mobile device location based on the assigned weight. The position point solution is constrained by the classification of each position point.

Claims

1. A method of determining a mobile device location, the method comprising:

receiving one or more signals from one or more transmitters;

measuring signal characteristics of the one or more received signals;

downloading data from a database corresponding to a defined region associated with the transmitters wherein the downloaded data comprises a plurality of position points, a classification of each position point, and expected signal characteristics for each position point;

determining a deviation between the measured signal characteristics and the expected signal characteristics for each position point;

weighting each position point based on the deviation;

constraining the plurality of weighted position points according to the classification of each position point; and

determining the mobile device location by selecting one position point of the constrained plurality of weighted position points as a position point solution corresponding to the mobile device location.

2. The method of claim 1 wherein the classification of each position point is as an interior position point or as an exterior position point based on an output of an interior-exterior classification algorithm.

3. The method of claim 2 wherein the interior-exterior classification algorithm is a morphological operation function.

4. The method of claim 2 wherein the interior-exterior classification algorithm is a multiple ray mechanism.

5. The method of claim 2 wherein constraining the plurality of weighted position points comprises constraining to interior classified position points.

6. The method of claim 2 wherein constraining the plurality of weighted position points comprises assigning zero weight to each exterior classified position point.

7. The method of claim 1 comprising:

determining transmitter identifying information from the received signals;

downloading transmitter location information based on the transmitter identifying information; and

estimating a mobile device position based at least in part on the transmitter location information;

and wherein the downloaded data corresponds to a map tile associated with the estimated mobile device position.

8. The method of claim 1 wherein selecting one position point as the position point solution comprises using a statistical measure of the weights assigned to the position points.

9. An apparatus for determining a mobile device location, the apparatus comprising:

a transceiver configured to receive one or more signals from one or more transmitters;

one or more processors communicatively coupled to the transceiver and configured to;

measure signal characteristics of the one or more received signals;

download data from a database corresponding to a defined region associated with the transmitters wherein the downloaded data comprises a plurality of position points, a classification of each position point, and expected signal characteristics for each position point;

determine a deviation between the measured signal characteristics and the expected signal characteristics for each position point;

weight each position point based on the deviation;

constrain the plurality of weighted position points according to the classification of each position point; and

determine the mobile device location by selecting one position point of the constrained plurality of weighted position points as a position point solution corresponding to the mobile device location; and

a memory communicatively coupled to the one or more processors.

10. The apparatus of claim 9 wherein the classification of each position point is as an interior position point or as an exterior position point based on an output of an interior-exterior classification algorithm.

11. The apparatus of claim 10 wherein the interior-exterior classification algorithm is a morphological operation function.

12. The apparatus of claim 10 wherein the interior-exterior classification algorithm is a multiple ray mechanism.

13. The apparatus of claim 10 wherein the plurality of weighted position points is constrained to interior classified position points.

14. The apparatus of claim 10 wherein the position point solution is constrained according to the classification of each position point by assigning zero weight to each exterior classified position point.

15. The apparatus of claim 10 wherein:

the one or more processors are configured to;

determine transmitter identifying information from the received signals;

download transmitter location information based on the transmitter identifying information; and

estimate a mobile device position based at least in part on the transmitter location information;

the memory is configured to store the downloaded transmitter location information; and

the downloaded data corresponds to a map tile associated with the estimated mobile device position.

16. The apparatus of claim 9 wherein selecting one position point as the position point solution comprises using a statistical measure of the weights assigned to the position points.

17. An apparatus for determining a mobile device location, the apparatus comprising:

means for receiving one or more signals from one or more transmitters;

means for measuring signal characteristics of the one or more received signals;

means for downloading data from a database corresponding to a defined region associated with the transmitters wherein the downloaded data comprises a plurality of position points, a classification of each position point, and expected signal characteristics for each position point;

means for determining a deviation between the measured signal characteristics and the expected signal characteristics for each position point;

means for weighting each position point based on the deviation;

means for constraining the plurality of weighted position points weighted according to the classification of each position point; and

means for determining the mobile device location by selecting one position point of the constrained plurality of weighted position points as a position point solution corresponding to the mobile device location.

18. The apparatus of claim 17 wherein the classification of each position point is as an interior position point or as an exterior position point based on an output of an interior-exterior classification algorithm.

19. The apparatus of claim 18 wherein the interior-exterior classification algorithm is a morphological operation function.

20. The apparatus of claim 18 wherein the interior-exterior classification algorithm is a multiple ray mechanism.

21. The apparatus of claim 18 wherein the means for constraining comprises means for constraining to interior classified position points.

22. The apparatus of claim 18 wherein the position point solution is constrained according to the classification of each position point by assigning zero weight to each exterior classified position point.

23. The apparatus of claim 19 comprising:

means for determining transmitter identifying information from the received signals;

means for downloading transmitter location information based on the transmitter identifying information; and

means for estimating a mobile device position based at least in part on the transmitter location information; and

wherein the downloaded data corresponds to a map tile associated with the estimated mobile device position.

24. The apparatus of claim 17 wherein selecting one position point as the position point solution comprises using a statistical measure of the weights assigned to the position points.

25. A computer program product residing on a processor-readable non-transitory storage medium and comprising processor-readable instructions executable by one or more processors to:

receive one or more signals from one or more transmitters;

measure signal characteristics of the one or more received signals;

download data from a database corresponding to a defined region associated with the transmitters wherein the downloaded data comprises a plurality of position points, a classification of each position point, and expected signal characteristics for each position point;

determine a deviation between the measured signal characteristics and the expected signal characteristics for each position point;

weight each position point based on the deviation;

constrain the plurality of weighted position points according to the classification of each position point; and

determine a mobile device location by selecting one position point of the constrained plurality of weighted position points as a position point solution corresponding to the mobile device location.

26. The computer program product of claim 25 wherein the classification of each position point is as an interior position point or as an exterior position point based on an output of an interior-exterior classification algorithm.

27. The computer program product of claim 26 wherein the interior-exterior classification algorithm is a morphological operation function.

28. The computer program product of claim 26 wherein the interior-exterior classification algorithm is a multiple ray mechanism.

29. The computer program product of claim 26 wherein plurality of weighted position points is constrained to interior classified position points.

30. The computer program product of claim 26 wherein the position point solution is constrained according to the classification of each position point by assigning zero weight to each exterior classified position point.

31. The computer program product of claim 25 further comprising processor-readable instructions executable by the one or more processors to:

determine transmitter identifying information from the received signals;

download transmitter location information based on the transmitter identifying information; and

estimate a mobile device position based at least in part on the transmitter location information; and

wherein the downloaded data corresponds to a map tile associated with the estimated mobile device position.

32. The computer program product of claim 25 wherein selecting one position point as the position point solution comprises using a statistical measure of the weights assigned to the position points.