Method and apparatus for mobile location determination

Patent metadata

Field	Value
Publication number	US-9749780-B2
Application number	US-201213983414-A
Country	US
Kind code	B2
Filing date	Jan 11, 2012
Priority date	Feb 5, 2011
Publication date	Aug 29, 2017
Grant date	Aug 29, 2017

Abstract

A method of generating a user?s location using a mobile device. The method comprises, determining a signal snapshot on the mobile device, the signal snapshot describing characteristics of unregulated radio frequency (RF) transmissions detectable by the mobile device. Generating the user?s location on the mobile device using the signal snapshot and at least one additional input from the mobile device. The generating and determining are iteratively repeated. The unregulated RF transmission can comprise WiFi signals.

First claim

What is claimed is:

1. A method comprising:
obtaining, by a mobile device from a server computer, a signal snapshot associated with a cell within a grid of contiguous cells that divide a map of an indoor space, where the cell is associated with a location in the indoor space and the signal snapshot includes one or more statistical parameters describing a probability distribution of received signal strength measurements of radio frequency (RF) transmissions from access points within the indoor space;
adjusting the statistical parameters based on observations of RF transmissions from one or more neighboring cells in the grid of cells;
obtaining, by the mobile device while the mobile device is operating in the indoor space, a set of received signal strength measurements of RF transmissions from the access points within the indoor space;
receiving, by the mobile device, input from one or more sensors of the mobile device, wherein the one or more sensors include at least one of an accelerometer, gyro or magnetometer;
applying, by the mobile device, one or more fit functions to the set of received signal strength measurements, the input and a path history associated with the indoor space, wherein applying one or more fit functions to the set of received signal strength measurements includes fitting the set of received signal strength measurements to the probability distribution using the one or more statistical parameters; and

determining a location of the mobile device in the indoor space based on a result of applying the one or more fit functions to the set of received signal strength measurements, the input and the path history associated with the indoor space.

2. The method of claim 1 , wherein the one or more statistical parameters include a mean and variance of the probability distribution.

3. The method of claim 1 , wherein the grid is associated with at least one occupancy value which indicates one or more areas in the indoor space that are walkable or not walkable.

4. The method of claim 1 , wherein the cell is initialized with statistical parameters associated with a plurality of cells in the grid.

5. A mobile device comprising:
a receiver;
one or more sensors; and
a processor operable to:
obtain, by the receiver, a signal snapshot associated with a cell within a grid of contiguous cells that divide a map of an indoor space, where the cell is associated with a location in the indoor space and the signal snapshot includes one or more statistical parameters describing a probability distribution of received signal strength measurements of radio frequency (RF) transmissions from access points within the indoor space;

adjust the statistical parameters based on observations of RF transmissions from one or more neighboring cells in the grid of cells;
obtain, by the receiver while the mobile device is operating in the indoor space, a set of received signal strength measurements of RF transmissions from the access points within the indoor space;
receive input from the one or more sensors of the mobile device, wherein the one or more sensors include at least one of an accelerometer, gyro or magnetometer;

apply one or more fit functions to the set of received signal strength measurements, the input and a path history associated with the indoor space, wherein applying the one or more fit functions to the set of received signal strength measurements includes fitting the set of received signal strength measurements to the probability distribution using the one or more statistical parameters; and
determining a location of the mobile device in the indoor space based on a result of applying the one or more fit functions to the set of received signal strength measurements, the input and the path history associated with the indoor space.

6. The mobile device of claim 5 , wherein the one or more statistical parameters include a mean and variance of the probability distribution.

7. The mobile device of claim 5 , wherein the grid is associated with at least one occupancy value which indicates one or more areas in the indoor space that are walkable or not walkable.

8. The mobile device of claim 5 , wherein the cell is initialized with statistical parameters associated with a plurality of cells in the grid.

9. A non-transitory, computer-readable storage medium having instructions stored thereon, which, when executed by one or more processors of a mobile device, causes the one or more processors to perform operations comprising:
obtaining, by the mobile device from a server computer, a signal snapshot associated with a cell within a grid of contiguous cells that divide a map of an indoor space, where the cell is associated with a location in the indoor space and the signal snapshot includes one or more statistical parameters describing a probability distribution of received signal strength measurements of radio frequency (RF) transmissions from access points within the indoor space;
adjusting the statistical parameters based on observations of RF transmissions from one or more neighboring cells in the grid of cells;
obtaining, by the mobile device while the mobile device is operating in the indoor space, a set of received signal strength measurements of RF transmissions from the access points within the indoor space;
receiving, by the mobile device, input from one or more sensors of the mobile device, wherein the one or more sensors include at least one of an accelerometer, gyro or magnetometer;
applying, by the mobile device, one or more fit functions to the set of received signal strength measurements, the input and a path history associated with the indoor space, wherein applying the one or more fit functions to the set of received signal strength measurements includes fitting the set of received signal strength measurements to the probability distribution using the one or more statistical parameters; and
determining a location of the mobile device in the indoor space based on a result of applying the one or more fit functions to the set of received signal strength measurements, the input and the path history associated with the indoor space.

10. The non-transitory, computer-readable storage medium of claim 9 , wherein the one or more statistical parameters include a mean and variance of the probability distribution.

11. The non-transitory, computer-readable storage medium of claim 9 , wherein the grid is associated with at least one occupancy value which indicates one or more areas in the indoor space that are walkable or not walkable.

12. The non-transitory, computer-readable storage medium of claim 9 , wherein the cell is initialized with statistical parameters associated with a plurality of cells in the grid.

Assignees

• Huang Joseph Ding-Jiu
• Millman David Benjamin
• Apple Inc

Inventors

• Huang Joseph Ding-Jiu
• Millman David Benjamin

Classifications

• G01S5/0264

  at least one of the systems being a non-radio wave positioning system · CPC title

• G01S5/02521

  using a radio-map · CPC title

• G06Q30/0623

  by investigating goods or services · CPC title

• H04W64/00 Primary

  Locating users or terminals {or network equipment} for network management purposes, e.g. mobility management · CPC title

• G01S5/0263

  by combining or switching between positions derived from two or more separate positioning systems · CPC title