Sensing and analysis of ambient contextual signals for discriminating between indoor and outdoor locations

• US 7,397,357 B2
• Filed: 11/09/2006
• Issued: 07/08/2008
• Est. Priority Date: 11/22/2004
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Horvitz, Eric J., Krumm, John C., Hariharan, Ramaswamy
• Primary Examiner(s): TRIEU, VAN THANH
• Application Number:
  US11/558,410
• Publication Number:
  US 20070085673A1
• Time in Patent Office: 607 Days
• Field of Search: 340/500, 340/501, 340/506, 340/517, 340/524, 340/539.13, 340/539.22, 340/539.28, 340/541, 455/41.2, 455/550.1, 455/567, 715/716, 715/719
• US Class Current: 340/501
• CPC Class Codes: G01W 1/17 Catathermometers for measuring "cooling value" related either to weather conditions or to comfort of other human environment
• CPC Class Codes: H04M 1/72454 according to context-related or environment-related conditions
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Methods and systems that determine automatically the likelihood that a device is inside or outside of a structure or building. The system uses one or more sensors to detect ambient conditions, and make the determination. The inference can be used to save power or suppress services from certain devices, which are irrelevant, cannot be used effectively, or do not function under certain circumstances. In support thereof, the system includes one or more context sensors that measure parameters associated probabilistically with the context of a device. A context computing component considers one or more context sensors and facilitates determination of ideal actions, policies, and situations associated with the device. A service provided by the subject invention is the inference from one or more available observations the probability that the device is inside versus outside.

Claims

1. A system that facilitates determination of a device context, comprising:

a context sensor that measures a parameter of a first context of a device; and

a context computing component that interfaces to the context sensor and facilitates determination of a change from the first context to a second context, wherein knowledge of such context transition is used to save power in certain devices by powering the devices off; and

wherein the context sensor is part of a sensing system that includes a GPS subsystem which is activated periodically to sense GPS signals, where the absence of GPS signals facilitates powering the GPS subsystem into a mode where the GPS subsystem only turns on periodically to probe for GPS signals and if no signals are sensed, the GPS subsystem is turned off after the periodic probes.

2. The system of claim 1, wherein the context sensor senses at least one of temperature, humidity, and pressure.

3. The system of claim 1, wherein the context sensor senses at least one of electromagnetic wave frequency and images.

4. The system of claim 1, wherein the context computing component infers that the device is inside or outside.

5. The system of claim 1, wherein the context sensor includes a GPS (Global Positioning System) receiver that facilitates determining the first context of the device based on receiving a GPS signal.

6. The system of claim 1, wherein the context sensor includes a GPS receiver that facilitates determining speed of the device based on receiving GPS location signals from at least two locations.

7. The system of claim 1, wherein the parameter measured by the context sensor powers on at least one of a GPS subsystem of the device and the device.

8. The system of claim 1, wherein the parameter indicates that a user of the device is available for interactive communications.

9. The system of claim 1, wherein data the represents the change from the first context to the second context is used to add metadata to a digital photograph.

10. The system of claim 9, wherein the metadata is used to filter the digital photograph from a plurality of photographs during a search process.

11. The system of claim 9, wherein the metadata includes information related to whether the photograph was taken indoors or outdoors.

12. The system of claim 1, further comprising an artificial intelligence component that employs a probabilistic and/or statistical-based analysis to prognose or infer an action that a user desires to be automatically performed.

13. A computer readable medium having computer-executable instructions for performing a method of determining context of a portable computing device, comprising:

measuring a first parameter of a first context of the portable computing device;

determining a second parameter of a second context of the portable computing device; and

computing a probability inference based on the first and second parameters that the portable computing device moved from the first context to the second context and turning off a component of the device based on the inference;

wherein location information is longitude/latitude data that is automatically accessed via a network and entered to facilitate determination of the device context.

14. The computer readable medium of claim 13, further comprising accessing at least one of GPS and weather information to derive the probability inference.

15. A method of determining context of a portable computing device, comprising:

determining a probability distribution of a first temperature of a first context of the portable computing device;

measuring a second temperature of a second context of the portable computing device; and

computing a probability inference based on the first and second temperatures that the portable computing device moved from the first context to the second context, wherein the probability inference is determined from at least one of a measured ambient temperature, and expected temperature inside a structure, and a temperature outside the structure derived from interpolation, and wherein the temperature outside the structure is derived by accessing longitude/latitude data.

16. The method of claim 15, wherein the first temperature is determined outside of a structure by accessing weather information associated with a geographic location of the first context.

17. The method of claim 15, wherein the first temperature is determined outside of a structure by interpolating weather information obtained by accessing weather stations.

18. The method of claim 15, further comprising deriving a probability distribution for an expected third temperature of the second context.