Method for estimating the position of a mobile station using TOA, AOA, and doppler-shift

Patent metadata

Field	Value
Publication number	US-9880259-B2
Application number	US-201514981100-A
Country	US
Kind code	B2
Filing date	Dec 28, 2015
Priority date	Oct 29, 2015
Publication date	Jan 30, 2018
Grant date	Jan 30, 2018

Abstract

A method for estimating the position of a mobile station (MS) comprising the following steps: physically moving the MS at a constant velocity v in an environment comprising S stationary scatterers; wirelessly transmitting N uplink communication signals from a transmitter physically mounted to the MS; receiving each of the N uplink signals via D distinct paths at a fixed-location base station (BS); recording with the BS a time of arrival (TOA) τ, an angle-of-arrival (AOA) θ, and a Doppler-shifted frequency (DSF) of each received uplink signal; estimating the location of the MS using a least squares algorithm based on the TOA, the AOA, and the DSF.

First claim

I claim:

1. A method for estimating the position of a mobile station (MS) comprising the following steps:
physically moving the MS at a constant velocity v in an environment comprising S stationary scatterers;
wirelessly transmitting N uplink communication signals from a transmitter physically mounted to the MS;
receiving each of the N uplink signals via D distinct paths at a fixed-location base station (BS);
recording with the BS a time of arrival (TOA) τ, an angle-of-arrival (AOA) θ, and a Doppler-shifted frequency (DSF) of each received uplink signal;
estimating a location of S scatterers using a system of linear equations;
estimating the speed v of the MS using a system of linear equations; and
estimating the location of the MS using a least squares algorithm based on the TOA, the AOA, and the DSF.

2. The method of claim 1 , wherein the MS moves through line-of-sight (LOS) and non-line-of-sight (NLOS) zones within the environment.

3. The method of claim 2 , wherein each received NLOS uplink signal undergoes a single-bounce reflection with one stationary scatterer.

4. The method of claim 3 , wherein the least squares algorithm comprises the following step:
estimating the location of the MS using nonlinear least squares.

5. The method of claim 4 , wherein the clocks on the BS and the MS are synchronized in time and frequency.

6. The method of claim 3 , wherein each reflection comprises specular reflection.

7. The method of claim 2 , wherein every received uplink signal is treated by the BS as if every received uplink signal followed an NLOS propagation path regardless of the action propagation path.

8. The method of claim 1 , wherein the environment comprises only non-line-of-sight (NLOS) propagation paths.

9. The method of claim 8 , wherein each received uplink signal undergoes a single-bounce reflection with one stationary scatterer.

10. The method of claim 9 , wherein the least squares algorithm comprises the following step:
estimating the location of the MS using nonlinear least squares.

11. The method of claim 10 , wherein the clocks on the BS and the MS are synchronized in time and frequency.

12. The method of claim 9 , where in each reflection contains specular reflection.

13. A method for estimating the position of a mobile station (MS) comprising the following steps:
physically moving the MS at a constant velocity v through line-of-sight (LOS) and non-line-of-sight (NLOS) zones within an environment comprising S stationary scatterers;
wirelessly transmitting N uplink communication signals from a transmitter physically mounted to the MS;
receiving at least 2 N uplink signals at a fixed-location base station (BS), wherein every received uplink signal is treated by the BS as if every received uplink signal followed an NLOS propagation path regardless of the actual propagation path;
recording with the B S a time of arrival (TOA) τ, an angle-of-arrival (AOA) θ, and a Doppler-shifted frequency (DSF) of each received uplink signal;
estimating a location of S scatterers using a system of linear equations;
estimating the speed v of the MS using a system of linear equations; and
estimating the location of the MS using a least squares algorithm based on the TOA, the AOA, and the DSF.

14. The method of claim 13 , wherein the clocks on the BS and the MS are synchronized in time and frequency.

Assignees

• Spawar Systems Ct Pacific
• The United States of America as represented by Scretary of the Navy

Inventors

• Ramlall Rohan Yash

Classifications

• G01S5/0273

  using multipath or indirect path propagation signals in position determination · CPC title

• G01S5/06 Primary

  Position of source determined by co-ordinating a plurality of position lines defined by path-difference measurements (G01S5/12 takes precedence) · CPC title