Power saving during sensor-assisted navigation

• US 9,618,351 B1
• Filed: 03/26/2015
• Issued: 04/11/2017
• Est. Priority Date: 03/26/2015
• Status: Active Grant

• Current Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Original Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Inventors: Mahapatra, Abinash
• Primary Examiner(s): Soofi, Yazan
• Application Number:
  US14/669,585
• Time in Patent Office: 747 Days
• Field of Search: 701412, 701468, 701469
• CPC Class Codes: G01C 21/10 by using measurements of speed or acceleration G01C21/24, G01C21/26 take precedence
• CPC Class Codes: G01C 21/1652 with ranging devices, e.g. LIDAR or RADAR
• CPC Class Codes: G01C 21/1656 with passive imaging devices, e.g. cameras
• CPC Class Codes: G01C 21/188 for accumulated errors, e.g. by coupling inertial systems with absolute positioning systems
• CPC Class Codes: G01C 21/30 Map- or contour-matching
• CPC Class Codes: G01C 21/3469 Fuel consumption; Energy use; Emission aspects
• CPC Class Codes: G01C 21/3605 Destination input or retrieval
• CPC Class Codes: G01C 21/3626 Details of the output of route guidance instructions traffic control systems for road vehicles involving transmission of navigation instructions to the vehicle G08G1/0968
• CPC Class Codes: G01C 21/3667 Display of a road map G01C21/3614 takes precedence; guidance using 3D or perspective road maps G01C21/3635

Abstract

Methods and apparatuses for power saving during sensor-assisted Global Positioning System (GPS) navigation using a mobile device are presented. The methods may include receiving location improvement data for a geographic location, the location improvement data including a value corresponding to improvement in accuracy for location data for the geographic location. The mobile device may utilize the location improvement data to determine whether to utilize inertial sensors in the mobile device to improve the accuracy of the position fix.

Claims

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

receiving location improvement data for a geographic location, the location improvement data including a value corresponding to improvement in accuracy for location data for the geographic location, wherein the value is determined by;

computing a first error range of first location data for the geographic location generated using a Global Positioning System (GPS) receiver in combination with sensor data;

computing a second error range of second location data for the geographic location generated using only the GPS receiver; and

computing a margin of improvement between the first error range and the second error range;

determining that the value is equal to or greater than a sensor enablement threshold criterion for the geographic location; and

enabling one or more sensors for use in location determination when at or near the geographic location.

2. The method of claim 1, further comprising:

enabling one or more inertial sensors including an accelerometer or a gyroscope or a barometer.

3. The method of claim 1, further comprising:

receiving location improvement data for the geographic location, the location improvement data including the value corresponding to a percentage proportionate to how much more accurate the first location data is at the geographic location compared to the second location data at the geographic location.

4. The method of claim 1, further comprising:

receiving location improvement data comprising map data indicative of a first map of a geographic region including the geographic location, the map data comprising at least one designation to be overlaid on a visual representation of the geographic region, a first designation of the at least one designation prescribing utilization of the sensor data in combination with GPS navigation when navigating in a first location in an area overlaid by the first designation.

5. The method of claim 4, wherein the at least one designation includes a second designation overlaid in a first non-overlapping area with the first designation on the visual representation of the geographic region and prescribing use of GPS navigation without utilizing the sensor data when navigating in a second location in an area overlaid by the second designation.

6. The method of claim 5, wherein the at least one designation includes a third designation overlaid in a second non-overlapping area with the first and second designations on the visual representation of the geographic region and prescribing:

utilization of sensor data in combination with GPS navigation when navigating in a third location in an area overlaid by the third designation and when a first condition is satisfied; and

non-utilization of the sensor data with GPS navigation when navigating in the third location and when the first condition is not satisfied.

7. The method of claim 6, wherein the first condition comprises a determination that a battery life of the mobile device exceeds a predetermined threshold.

8. The method of claim 6, wherein the first condition comprises a determination that GPS signals from fewer than five GPS satellites are being received by the mobile device.

9. The method of claim 6, wherein the first condition comprises a determination that a signal strength of a GPS satellite at the mobile device exceeds a predetermined threshold.

10. The method of claim 1, further comprising:

receiving location improvement data comprising data indicative of a second map of the geographic region including the geographic location, the second map comprising a first value indicative of a first increase in accuracy of the first estimated location, at the geographic location, over the second estimated location, at the geographic location.

11. The method of claim 10, further comprising:

receiving location improvement data comprising data indicative of a third map of the geographic region including the geographic location, the third map comprising a second value indicative of a second increase in accuracy of the first estimated location, at the geographic location, over the second estimated location, at the geographic location, when the mobile device satisfies a navigation condition.

12. The method of claim 11, wherein the navigation condition comprises a determination that a signal strength from a GPS satellite falls below a predetermined threshold.

13. The method of claim 11, wherein the navigation condition comprises a determination that the mobile device receives GPS data from fewer than a predetermined number of GPS satellites.

14. A mobile device comprising:

a global positioning system (GPS) receiver configured to provide timing measurements for use in a GPS navigation application;

a data receiver;

one or more sensors configured to provide sensor data; and

a processor operatively coupled to the GPS receiver, the data receiver, and the one or more sensors;

wherein the data receiver is configured to;

receive location improvement data for a geographic location, the location improvement data including a value corresponding to improvement in accuracy for location data for the geographic location, wherein the value is determined by;

computing a first error range of first location data for the geographic location generated using a Global Positioning System (GPS) receiver in combination with sensor data;

computing a second error range of second location data for the geographic location generated using only the GPS receiver; and

computing a margin of improvement between the first error range and the second error range;

wherein the processor is configured to;

determine that the value is equal to or greater than a sensor enablement threshold criterion for the geographic location; and

enable the one or more sensors for use in location determination when at or near the geographic location.

15. The mobile device of claim 14, wherein the value comprises a percentage proportionate to how much more accurate the first location data is at the geographic location compared to the second location data at the geographic location.

16. The mobile device of claim 14, wherein the location improvement data comprises map data indicative of a first map of a geographic region including the geographic location, the map data comprising:

at least one designation to be overlaid on a visual representation of the geographic region, a first designation of the at least one designation prescribing utilization of the sensor data in combination with the GPS navigation application when navigating in a first location in an area overlaid by the first designation; and

a second designation overlaid in a first non-overlapping area with the first designation on the visual representation of the geographic region and prescribing use of GPS navigation without utilizing the sensor data when navigating in a second location in an area overlaid by the second designation.

17. The mobile device of claim 16, wherein the at least one designation includes a third designation overlaid in a second non-overlapping area with the first and second designations on the geographic region and prescribing:

utilization of sensor data in combination with the GPS navigation application when navigating in an area overlaid by the third designation and when a first condition is satisfied; and

non-utilization of sensor data with the GPS navigation application when navigating in the third location and when the first condition is not satisfied.

18. The mobile device of claim 14, wherein the one or more sensors comprises an accelerometer, a gyroscope, or a barometer.

19. The mobile device of claim 14, wherein the location improvement data comprises data indicative of a second map of the geographic region including the geographic location, the second map comprising a first value indicative of a first increase in accuracy of the first estimated location, at the geographic location, over the second estimated location, at the geographic location.

20. The mobile device of claim 19, wherein the location improvement data comprises data indicative of a third map of the geographic region including the geographic location, the third map comprising a second value indicative of a second increase in accuracy of the first estimated location, at the geographic location, over the second estimated location, at the geographic location, when the mobile device satisfies a navigation condition.

21. A method of operating a mobile device, the method comprising:

receiving location improvement data for a geographic location, the location improvement data including;

a value corresponding to improvement in accuracy for location data for the geographic location, wherein the value is determined by comparing first location data for the geographic location generated using a Global Positioning System (GPS) receiver in combination with sensor data and second location data for the geographic location generated using only the GPS receiver;

map data indicative of a first map of a geographic region including the geographic location, the map data comprising;

at least one designation to be overlaid on a visual representation of the geographic region;

a first designation of the at least one designation prescribing utilization of the sensor data in combination with GPS navigation when navigating in a first location in an area overlaid by the first designation;

a second designation of the at least one designation overlaid in a first non-overlapping area with the first designation on the visual representation of the geographic region and prescribing use of GPS navigation without utilizing the sensor data when navigating in a second location in an area overlaid by the second designation; and

a third designation of the at least one designation overlaid in a second non-overlapping area with the first and second designations on the visual representation of the geographic region and prescribing;

utilization of sensor data in combination with GPS navigation when navigating in a third location in an area overlaid by the third designation and when a first condition is satisfied; and

non-utilization of the sensor data with GPS navigation when navigating in the third location and when the first condition is not satisfied;

determining that the value is equal to or greater than a sensor enablement threshold criterion for the geographic location; and

enabling one or more sensors for use in location determination when at or near the geographic location.