Radar odometry system and method

Patent metadata

Field	Value
Publication number	US-12153120-B2
Application number	US-202117446602-A
Country	US
Kind code	B2
Filing date	Aug 31, 2021
Priority date	Aug 31, 2020
Publication date	Nov 26, 2024
Grant date	Nov 26, 2024

Abstract

A method for determining a position of a vehicle is provided. First and second signals having first and second frequencies are transmitted towards a target. First and second reflected signals corresponding to the first and second signals reflected from the target are received at first and second antennae, respectively. A first frequency difference between the first signal and the first reflected signal is determined. The first frequency difference corresponds to a first range between the vehicle and target. A second frequency difference between the second pulsed signal and the second reflected signal is determined. The second frequency difference corresponds to a second range between the vehicle and target. A vehicle velocity is based on the first range and the second range. A position of the vehicle is determined based on the velocity.

First claim

What is claimed is:

1. A method for determining a position of a vehicle having a transmitter and at least two antenna each associated with a receiver, the method comprising:
(A) transmitting a first pulsed signal towards a target, the first pulsed signal having a first frequency;
(B) receiving a first reflected signal from the target at a first antenna of the at least two antenna, the first reflected signal corresponding to the first pulsed signal reflected from the target;
(C) determining a first frequency difference between the first pulsed signal and the first reflected signal, the first frequency difference corresponding to a first range between the vehicle and the target, the first frequency difference having a first value;
(D) transmitting a second pulsed signal towards the target, the second pulsed signal having a second frequency;
(E) receiving a second reflected signal from the target at a second antenna of the at least two antenna, the second reflected signal corresponding to the second pulsed signal reflected from the target;
(F) determining a second frequency difference between the second pulsed signal and the second reflected signal, the second frequency difference corresponding to a second range between the vehicle and the target, the second frequency difference having a second value greater than the first value;
(G) comparing the first value with the second value;
(H) determining that a position associated with the second reflected signal is a nadir range pixel, the nadir range pixel corresponding to the second range; and
(I) determining a velocity of the vehicle based on the first range and the second range, the determining the position is based on the velocity and the position corresponds to a vehicle position.

2. The method of claim 1 , further comprising beamforming the velocity of the vehicle.

3. The method of claim 1 , further comprising determining an angle between the vehicle and the target based on the first range and the second range.

4. The method of claim 3 , further comprising determining a doppler with a Fourier Transform of the velocity.

5. The method of claim 1 , further comprising:
performing operations (A)-(F) in an azimuth direction; and
performing operations (A)-(F) in an elevation direction.

6. The method of claim 5 , further comprising beamforming the velocity for each of the azimuth direction and the elevation direction.

7. The method of claim 1 , wherein the first frequency is determined using stretch processing between the first pulsed signal and the first reflected signal and the second frequency is determined using stretch processing between the second pulsed signal and the second reflected signal.

8. The method of claim 1 , wherein the position is determined from the velocity by determining a Fourier Transform of the velocity.

9. A method for determining a position of a vehicle having a transmitter and at least two antenna each associated with a receiver, the method comprising:
(A) transmitting a first pulsed signal towards a target, the first pulsed signal having a first frequency;
(B) receiving a first reflected signal from the target at a first antenna of the at least two antenna, the first reflected signal corresponding to the first pulsed signal reflected from the target;
(C) determining a first frequency difference between the first pulsed signal and the first reflected signal, the first frequency difference corresponding to a first range between the vehicle and the target;
(D) transmitting a second pulsed signal towards the target, the second pulsed signal having a second frequency;
(E) receiving a second reflected signal from the target at a second antenna of the at least two antenna, the second reflected signal corresponding to the second pulsed signal reflected from the target;
(F) determining a second frequency difference between the second pulsed signal and the second reflected signal, the second frequency difference corresponding to a second range between the vehicle and the target;
(G) comparing the first range with the second range to determine an angle;
(H) determining a velocity of the vehicle based on the first range and the second range; and
(I) determining a position of the vehicle based on the velocity and the angle.

10. The method of claim 9 , further comprising beamforming the velocity of the vehicle.

11. The method of claim 9 , further comprising:
determining a doppler with a Fourier Transform of the velocity.

12. The method of claim 9 , further comprising:
performing operations (A)-(F) in an azimuth direction; and
performing operations (A)-(F) in an elevation direction.

13. The method of claim 12 , further comprising beamforming the velocity for each of the azimuth direction and the elevation direction.

14. The method of claim 9 , wherein the first frequency is determined using stretch processing between the first pulsed signal and the first reflected signal and the second frequency is determined using stretch processing between the second pulsed signal and the second reflected signal.

15. The method of claim 9 , wherein the position is determined from the velocity by determining a Fourier Transform of the velocity.

16. A system for determining a position of a vehicle, the system comprising:
a transmitter configured to:
transmit a first pulsed signal towards a target, the first pulsed signal having a first frequency; and
transmit a second pulsed signal towards the target, the second pulsed signal having a second frequency;

a receiver configured to:
receive a first reflected signal from the target at a first antenna of at least two antenna, the first reflected signal corresponding to the first pulsed signal reflected from the target; and
receive a second reflected signal from the target at a second antenna of the at least two antenna, the second reflected signal corresponding to the second pulsed signal reflected from the target;

a processor configured to:
determine a first frequency difference between the first pulsed signal and the first reflected signal, the first frequency difference corresponding to a first range between the vehicle and the target, the first frequency difference having a first value;
determine a second frequency difference between the second pulsed signal and the second reflected signal, the second frequency difference corresponding to a second range between the vehicle and the target, the second frequency difference having a second value greater than the first value;
compare the first value with the second value;
determine that a position associated with the second reflected signal is a nadir range pixel, the nadir range pixel corresponding to the second range; and
determine a velocity of the vehicle based on the first range and the second range, the determining the position is based on the velocity and the position corresponds to a vehicle position.

17. The system of claim 16 , wherein the processor is configured to beamform the velocity of the vehicle.

18. The system of claim 16 , wherein the processor is configured to:
determine an angle between the vehicle and the target based on the first range and the second range; and
determine a doppler with a Fourier Transform of the velocity.

19. The system of claim 16 , wherein processor is further configured to:
determine the first frequency using stretch processing between the first pulsed signal and the first reflected signal; and
determine the second frequency using stretch processing between the second pulsed signal and the second reflected si

Assignees

• Joby Aero Inc

Inventors

• Burghardt Michael
• Bhatti Jahshan
• Smith Donnie

Classifications

• G01S7/295

  Means for transforming co-ordinates or for evaluating data, e.g. using computers · CPC title

• G01S13/582

  adapted for simultaneous range and velocity measurements · CPC title

• G01S13/347

  using more than one modulation frequency · CPC title

• G01S13/584

  adapted for simultaneous range and velocity measurements · CPC title

• G01S13/931

  of land vehicles · CPC title