Step size and step heading correction for positioning in wireless network

Patent metadata

Field	Value
Publication number	US-2024369672-A1
Application number	US-202418639863-A
Country	US
Kind code	A1
Filing date	Apr 18, 2024
Priority date	May 4, 2023
Publication date	Nov 7, 2024
Grant date	—

Abstract

A method for estimating a position of a moving object comprises: storing one or more reference position estimates for the moving object in a first buffer; storing step information in a second buffer, the step information including one or more step sizes and one or more step headings; receiving a motion event signal indicating the moving object moves continuously with a bounded direction; correcting the step information based on the one or more reference position estimates in response to receiving the motion event signal; and estimating the position of the moving object using the corrected step information.

First claim

What is claimed is:

1 . A method for estimating a position of a moving object, the method comprising:
storing one or more reference position estimates for the moving object in a first buffer; storing step information in a second buffer, the step information including one or more step sizes and one or more step headings; receiving a motion event signal indicating the moving object moves continuously with a bounded direction; correcting the step information based on the one or more reference position estimates in response to receiving the motion event signal; and estimating the position of the moving object using the corrected step information.

2 . The method of claim 1 , wherein the correcting the step information comprises:
determining a first direction based on one or more step headings stored in the second buffer; determining a second direction based on a slope of a line derived from at least two reference position estimates stored in the first buffer; determining an offset using the first direction and the second direction; and correcting one or more step headings using the offset.

3 . The method of claim 1 , wherein the correcting the step information comprises:
determining a displacement based on a line derived from at least two reference position estimates stored in the first buffer; determining a scale factor based on the displacement and a sum of one or more step sizes stored in the second buffer; and correcting one or more step sizes using the scale factor.

4 . The method of claim 1 , further comprising:
storing one or more ranging measurements provided from a ranging device in a third buffer, the one or more ranging measurements including distances between the moving object and a set of anchor points.

5 . The method of claim 4 , wherein the correcting the step information comprises:
estimating positions of the moving object by filtering one or more ranging measurements stored in the third buffer using a damping filter; determining a third direction based on one or more step headings stored in the second buffer; determining a fourth direction based on a slope of a line derived from at least two estimated positions; determining an offset using the third direction and the fourth direction; and correcting one or more step headings using the offset.

6 . The method of claim 5 , wherein further comprising storing the estimated positions in a fourth buffer.

7 . The method of claim 5 , wherein the damping filter is initialized at a time which is prior to receiving the motion event signal.

8 . The method of claim 1 , wherein the motion event signal is received between two most recent reference position estimates.

9 . The method of claim 4 , wherein the step information stored in the second buffer and the one or more ranging measurements stored in the third buffer are generated between two most recent reference position estimates.

10 . The method of claim 1 , further comprising:
storing one or more sensor readings indicating orientation of the moving object in a fifth buffer, wherein the correcting the step information comprises:
determining a first orientation based on one or more sensor readings in the fifth buffer;
determining a second orientation based on a slope of a line derived from at least two reference position estimates stored in the first buffer;
determining an offset using the first orientation and the second orientation; and
determining a corrected orientation using the offset.

11 . A device for estimating a position of the device, comprising:
a sensor configured to generate step information, the step information including one or more step sizes and one or more step headings; and a processor coupled to the sensor, the processor configured to cause:
storing one or more reference position estimates for the device in a first buffer;
storing the step information generated from the sensor in a second buffer;
receiving a motion event signal indicating the device moves continuously with a bounded direction from the sensor;
correcting the step information based on the one or more reference position estimates in response to receiving the motion event signal; and
estimating the position of the device using the corrected step information.

12 . The device of claim 11 , wherein the correcting the step information comprises:
determining a first direction based on one or more step headings stored in the second buffer; determining a second direction based on a slope of a line derived from at least two reference position estimates stored in the first buffer; determining an offset using the first direction and the second direction; and correcting one or more step headings using the offset.

13 . The device of claim 11 , wherein the correcting the step information comprises:
determining a displacement based on a line derived from at least two reference position estimates stored in the first buffer; determining a scale factor based on the displacement and a sum of one or more step sizes stored in the second buffer; and correcting one or more step sizes using the scale factor.

14 . The device of claim 11 , further comprising:
a ranging device configured to generate one or more ranging measurements including distances between the device and a set of anchor points; and the processor is further configured to cause:
storing the one or more ranging measurements generated from the ranging device in a third buffer.

15 . The device of claim 11 , wherein the correcting the step information comprises:
estimating positions of the device by filtering one or more ranging measurements stored in the third buffer using a damping filter; determining a third direction based on one or more step headings stored in the second buffer; determining a fourth direction based on a slope of a line derived from at least two estimated positions; determining an offset using the third direction and the fourth direction; and correcting one or more step headings using the offset.

16 . The device of claim 15 , wherein the correcting the step information further comprises storing the estimated positions in a fourth buffer.

17 . The device of claim 15 , wherein the damping filter is initialized at a time which is prior to receiving the motion event signal.

18 . The device of claim 11 , wherein the motion event signal is received between two most recent reference position estimates.

19 . The device of claim 14 , wherein the step information stored in the second buffer and the one or more ranging measurements stored in the third buffer are generated between two most recent reference position estimates.

20 . The device of claim 11 , wherein the processor is further configured to cause:
storing one or more sensor readings indicating orientation of the moving object in a fifth buffer, wherein the correcting the step information comprises:
determining a first orientation based on one or more sensor readings in the fifth buffer;
determining a second orientation based on a slope of a line derived from at least two reference position estimates stored in the first buffer;
determining an offset using the first orientation and the second orientation; and
determining a corrected orientation using the offset.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Jurdi Rebal
• Dawar Neha
• Zhu Yuming
• Zhang Jianzhong
• Han Johnny Kyu-Hui

Classifications

• G01S7/006

  using shared front-end circuitry, e.g. antennas (G01S13/765, G01S13/825 take precedence) · CPC title

• G01S13/878

  Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector (G01S13/874 takes precedence) · CPC title

• G01S13/723

  by using numerical data · CPC title

• G01S2205/02

  Indoor · CPC title

• G01S5/0294

  Trajectory determination or predictive filtering, e.g. target tracking or Kalman filtering · CPC title