Survey Techniques for Generating Location Fingerprint Data

• US 20140213299A1
• Filed: 01/31/2013
• Published: 07/31/2014
• Est. Priority Date: 01/31/2013
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Marti, Lukas M., Mayor, Robert, Ma, Shannon M.
• Granted Patent: US 9,198,003 B2
• Time in Patent Office: Days
• US Class Current: 455/456.3
• CPC Class Codes: G01C 21/206 specially adapted for indoor navigation
• CPC Class Codes: G01S 5/02525 Gathering the radio frequency fingerprints
• CPC Class Codes: G06F 3/048 Interaction techniques based on graphical user interfaces [GUI]
• CPC Class Codes: H04M 1/00 Substation equipment, e.g. for use by subscribers subscriber services or facilities provided at exchanges H04M3/00; prepayment telephone coin boxes H04M17/00; current supply arrangements H04M19/08
• CPC Class Codes: H04W 4/021 Services related to particular areas, e.g. point of interest [POI] services, venue services or geofences
• CPC Class Codes: H04W 4/027 using movement velocity, acceleration information
• CPC Class Codes: H04W 4/38 for collecting sensor information
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

Surveying techniques for generating location fingerprint data are described. A mobile device can survey a venue by measuring, at multiple locations at the venue, signals from one or more signal sources. At each location, the mobile device can take multiple measurements of signals. The mobile device can take each measurement at a distinct orientation. The measurements can be used to determine expected measurements of the signals at the venue. Differences between the multiple measurements of signals can be used to determine a variance of the expected measurements. The expected measurements and variance can be designated as location fingerprint data for the venue. The location fingerprint data can be used by mobile devices for determining a location at the venue.

Claims

1. A method comprising:

providing a user interface for display on a mobile device, the user interface comprising a map of a venue, the venue comprising a space accessible by a pedestrian and one or more constraints of movement of the pedestrian in the space, the map configured to receive from a user an input placing a marker at a location on the map, wherein the location indicates a user-estimated location of the mobile device at the venue;

recording, by the mobile device, a first reading of a sensor of the mobile device and a second reading of the sensor, the first reading being associated with a first orientation of at least one of the user or the mobile device, the second reading being associated with a second orientation of at least one of the user or the mobile device, the first reading and the second reading of the sensor each measuring one or more signals received by the sensor at the location; and

determining a signal fingerprint of the location based on the first reading and the second reading, including controlling an effect of a body of the user on the signal fingerprint based on a difference between the first reading and second reading and a difference between the first orientation and the second orientation.

2. The method of claim 1, wherein the first orientation is perpendicular to or facing the second orientation.

3. The method of claim 1, wherein the one or more signals comprise a radio frequency (RF) signal.

4. The method of claim 3, wherein:

each of the one or more signals is from a wireless access point, and

recording the first reading and the second reading comprises configuring the sensor to scan channels of each wireless access point for at least a threshold time at each orientation, the threshold time being longer than a beacon interval of the wireless access point.

5. The method of claim 1, wherein determining the signal fingerprint of the location comprises determining:

a probability distribution of an expected reading of a sensor of another mobile device when the other mobile device is located at the location, and

a variance of the expected reading, wherein a magnitude of the variance corresponds to the difference between the first reading and second reading.

6. The method of claim 1, comprising:

recording, by the mobile device, a third reading of the sensor of the mobile device and a fourth reading of the sensor, the third reading being associated with a third orientation of at least one of the user or the mobile device, the fourth reading being associated with a fourth orientation of at least one of the user or the mobile device, each of the first, second, third, and fourth orientations being on a same Euclidian plane and facing east, south, west, and north on a local reference frame on the Euclidian plane, wherein determining the signal fingerprint of the location is further based on the third reading and the fourth reading.

7. A method, comprising:

providing a user interface for display on a mobile device, the user interface comprising a map of a venue, the venue comprising a space accessible by a pedestrian and one or more constraints of movement of the pedestrian in the space, the map configured to receive a first placement input placing an origin marker on the map and to receive a second placement input placing a destination marker on the map, wherein a location of each of the origin marker and the destination marker on the map respectively indicates a user-estimated starting point and a user-estimated ending point of movement of the mobile device at the venue;

recording first measurements from a sensor of the mobile device while the mobile device moves from the starting point to the ending point along a path defined by the starting point and the ending point, the first measurements comprising measurements of one or more signals received by the sensor;

recording second measurements from a sensor while the mobile device moves from the ending point to the starting point along the path;

determining a location on the path that is associated with at least one of the first measurements and at least one of the second measurements; and

providing the location, the at least one first measurements, and the at least one second measurements, to a location server for determining, using interpolation, a signal fingerprint of the location.

8. The method of claim 7, wherein the one or more signals comprise a radio frequency (RF) signal.

9. The method of claim 8, wherein:

each of the one or more signals is from a wireless access point, and

recording the first measurements and the second measurements comprises scanning selected channels of each wireless access point, the channels being selected based on whether the channels overlap with other channels.

10. The method of claim 9, comprising:

while scanning a selected channel, detecting a beacon signal on a neighboring channel; and

recording a measurement of the beacon signal as one of the first measurements or one of the second measurements.

11. The method of claim 9, comprising maximizing scan rate for the sensor.

12. The method of claim 8, wherein determining the signal fingerprint of the location comprises controlling an effect of a body of the user on the signal fingerprint based on a difference between the first measurements and the second measurements.

13. The method of claim 8, wherein determining the signal fingerprint of the location comprises determining a probability distribution of an expected reading of a sensor of another mobile device at the location and a variance of the expected readings, wherein a magnitude of the variance corresponds to differences between the first measurements and second measurements.

14. The method of claim 8, wherein providing the user interface for display occurs after recording the first measurements and second measurements.

15. The method of claim 14, comprising determining the path based on the locations of the origin marker and the destination marker and the map according to the constraints of movements represented on the map.

16. The method of claim 15, wherein determining the path comprises:

determining a speed and a heading of the mobile device using a micro-electro-mechanical systems (MEMS) device of the mobile device; and

determining at least a portion of the path based on the origin marker, the speed and heading, and the constraints of the map.

17. The method of claim 7, comprising:

determining a length of the path;

based on the length, determining whether the mobile device moved at a constant speed from the starting point to the ending point and from the ending point to the starting point; and

adjusting a variance in the signal fingerprint based on the determining.

18. A method comprising:

providing a map user interface for display on a mobile device, the map user interface comprising a map of a venue, the map representing constraints of pedestrian movements at the venue, the map user interface being configured to receive a location input specifying a location of the mobile device at the venue, the location being relative to the venue;

upon receiving the location input, providing for display on the mobile device an orientation user interface, the orientation user interface comprising a first orientation user interface item and a second user interface item, each of the first orientation user interface item and second user interface item indicating a respective orientation of the mobile device, each orientation being a direction a surveyor carrying the mobile device faces;

recording, by the mobile device, a first measurement of a signal from a signal source at a first orientation in response to an input received through the first user interface item;

recording, by the mobile device, a second measurement of the signal from the signal source at a second orientation in response to an input received through the second user interface item, wherein attenuation of the signal caused by the surveyor carrying the mobile device in the first orientation is different from attenuation of the signal caused by the surveyor carrying the device in the second orientation; and

providing the first measurement and the second measurement in association with the location to a location server for determining location fingerprint data for the venue.

19. The method of claim 18, wherein the first orientation is perpendicular to the second orientation or faces the second orientation.

20. A storage device storing computer instructions operable to cause one or more processors to perform operations comprising:

providing a user interface for display on a mobile device, the user interface comprising a map of a venue, the venue comprising a space accessible by a pedestrian and one or more constraints of movement of the pedestrian in the space, the map configured to receive from a user an input placing a marker at a location on the map, wherein the location indicates a user-estimated location of the mobile device at the venue;

recording, by the mobile device, a first reading of a sensor of the mobile device and a second reading of the sensor, the first reading being associated with a first orientation of at least one of the user or the mobile device, the second reading being associated with a second orientation of at least one of the user or the mobile device, the first reading and the second reading of the sensor each measuring one or more signals received by the sensor at the location; and

determining a signal fingerprint of the location based on the first reading and the second reading, including controlling an effect of a body of the user on the signal fingerprint based on a difference between the first reading and second reading and a difference between the first orientation and the second orientation.

21. The storage device of claim 20, wherein the first orientation is perpendicular to or facing the second orientation.

22. The storage device of claim 20, wherein:

each of the one or more signals is a radio frequency (RF) signal from a wireless access point, and

recording the first reading and the second reading comprises configuring the sensor to scan channels of each wireless access point for at least a threshold time at each orientation, the threshold time being longer than a beacon interval of the wireless access point.

23. A storage device storing computer instructions operable to cause one or more processors to perform operations comprising:

providing a user interface for display on a mobile device, the user interface comprising a map of a venue, the venue comprising a space accessible by a pedestrian and one or more constraints of movement of the pedestrian in the space, the map configured to receive a first placement input placing an origin marker on the map and to receive a second placement input placing a destination marker on the map, wherein a location of each of the origin marker and the destination marker on the map respectively indicates a user-estimated starting point and a user-estimated ending point of movement of the mobile device at the venue;

recording first measurements from a sensor of the mobile device while the mobile device moves from the starting point to the ending point along a path defined by the starting point and the ending point, the first measurements comprising measurements of one or more signals received by the sensor;

recording second measurements from a sensor while the mobile device moves from the ending point to the starting point along the path;

determining a location on the path that is associated with at least one of the first measurements and at least one of the second measurements; and

providing the location, the at least one first measurements, and the at least one second measurements, to a location server for determining, using interpolation, a signal fingerprint of the location.

24. The storage device of claim 23, the operations comprising:

while scanning a selected channel, detecting a beacon signal on a neighboring channel; and

recording a measurement of the beacon signal as one of the first measurements or one of the second measurements.

25. The storage device of claim 23, the operations comprising maximizing scan rate for the sensor.

26. A storage device storing computer instructions operable to cause one or more processors to perform operations comprising:

providing a map user interface for display on a mobile device, the map user interface comprising a map of a venue, the map representing constraints of pedestrian movements at the venue, the map user interface being configured to receive a location input specifying a location of the mobile device at the venue, the location being relative to the venue;

upon receiving the location input, providing for display on the mobile device an orientation user interface, the orientation user interface comprising a first orientation user interface item and a second user interface item, each of the first orientation user interface item and second user interface item indicating a respective orientation of the mobile device, each orientation being a direction a surveyor carrying the mobile device faces;

recording, by the mobile device, a first measurement of a signal from a signal source at a first orientation in response to an input received through the first user interface item;

recording, by the mobile device, a second measurement of the signal from the signal source at a second orientation in response to an input received through the second user interface item, wherein attenuation of the signal caused by the surveyor carrying the mobile device in the first orientation is different from attenuation of the signal caused by the surveyor carrying the device in the second orientation; and

providing the first measurement and the second measurement in association with the location to a location server for determining location fingerprint data for the venue.

27. The storage device of claim 26, wherein the first orientation is perpendicular to the second orientation or faces the second orientation.

28. A system comprising:

one or more processors; and

a storage device storing computer instructions operable to cause the one or more processors to perform operations comprising;

providing a user interface for display on a mobile device, the user interface comprising a map of a venue, the venue comprising a space accessible by a pedestrian and one or more constraints of movement of the pedestrian in the space, the map configured to receive from a user an input placing a marker at a location on the map, wherein the location indicates a user-estimated location of the mobile device at the venue;

recording, by the mobile device, a first reading of a sensor of the mobile device and a second reading of the sensor, the first reading being associated with a first orientation of at least one of the user or the mobile device, the second reading being associated with a second orientation of at least one of the user or the mobile device, the first reading and the second reading of the sensor each measuring one or more signals received by the sensor at the location; and

determining a signal fingerprint of the location based on the first reading and the second reading, including controlling an effect of a body of the user on the signal fingerprint based on a difference between the first reading and second reading and a difference between the first orientation and the second orientation.

29. The system of claim 28, wherein the first orientation is perpendicular to or facing the second orientation.

30. The system of claim 28, wherein:

each of the one or more signals is a radio frequency (RF) signal from a wireless access point, and

recording the first reading and the second reading comprises configuring the sensor to scan channels of each wireless access point for at least a threshold time at each orientation, the threshold time being longer than a beacon interval of the wireless access point.

31. A system comprising:

one or more processors; and

a storage device storing computer instructions operable to cause the one or more processors to perform operations comprising;

providing a user interface for display on a mobile device, the user interface comprising a map of a venue, the venue comprising a space accessible by a pedestrian and one or more constraints of movement of the pedestrian in the space, the map configured to receive a first placement input placing an origin marker on the map and to receive a second placement input placing a destination marker on the map, wherein a location of each of the origin marker and the destination marker on the map respectively indicates a user-estimated starting point and a user-estimated ending point of movement of the mobile device at the venue;

recording first measurements from a sensor of the mobile device while the mobile device moves from the starting point to the ending point along a path defined by the starting point and the ending point, the first measurements comprising measurements of one or more signals received by the sensor;

recording second measurements from a sensor while the mobile device moves from the ending point to the starting point along the path;

determining a location on the path that is associated with at least one of the first measurements and at least one of the second measurements; and

providing the location, the at least one first measurements, and the at least one second measurements, to a location server for determining, using interpolation, a signal fingerprint of the location.

32. The system of claim 31, the operations comprising:

while scanning a selected channel, detecting a beacon signal on a neighboring channel; and

recording a measurement of the beacon signal as one of the first measurements or one of the second measurements.

33. The system of claim 31, the operations comprising maximizing scan rate for the sensor.

34. A system comprising:

one or more processors; and

a storage device storing computer instructions operable to cause the one or more processors to perform operations comprising;

providing a map user interface for display on a mobile device, the map user interface comprising a map of a venue, the map representing constraints of pedestrian movements at the venue, the map user interface being configured to receive a location input specifying a location of the mobile device at the venue, the location being relative to the venue;

upon receiving the location input, providing for display on the mobile device an orientation user interface, the orientation user interface comprising a first orientation user interface item and a second user interface item, each of the first orientation user interface item and second user interface item indicating a respective orientation of the mobile device, each orientation being a direction a surveyor carrying the mobile device faces;

recording, by the mobile device, a first measurement of a signal from a signal source at a first orientation in response to an input received through the first user interface item;

recording, by the mobile device, a second measurement of the signal from the signal source at a second orientation in response to an input received through the second user interface item, wherein attenuation of the signal caused by the surveyor carrying the mobile device in the first orientation is different from attenuation of the signal caused by the surveyor carrying the device in the second orientation; and

providing the first measurement and the second measurement in association with the location to a location server for determining location fingerprint data for the venue.

35. The system of claim 34, wherein the first orientation is perpendicular to the second orientation or faces the second orientation.