3D video-Doppler-radar (VIDAR) imaging system

• US 8,009,081 B2
• Filed: 10/21/2008
• Issued: 08/30/2011
• Est. Priority Date: 10/21/2008
• Status: Active Grant

• Current Assignee: Oculii Corp (Ambarella Incorporated)
• Original Assignee: Lang Hong, Steven Hong
• Inventors: Hong, Steven, Hong, Lang
• Primary Examiner(s): Sotomayor; John B
• Application Number:
  US12/255,081
• Publication Number:
  US 20100097262A1
• Time in Patent Office: 1,043 Days
• Field of Search: 342/52, 342 54- 55, 342/59
• US Class Current: 342/52
• CPC Class Codes: G01S 13/589 measuring the velocity vector
• CPC Class Codes: G01S 13/867 Combination of radar systems with cameras
• CPC Class Codes: G01S 13/87 Combinations of radar systems, e.g. primary radar and secondary radar
• CPC Class Codes: G01S 13/89 for mapping or imaging
• CPC Class Codes: G01S 19/14 specially adapted for specific applications
• CPC Class Codes: G01S 3/7864 T.V. type tracking systems

Abstract

A moving sensor suite for imaging a scene has three Doppler radars, two moving and one fixed, a fixed video camera and a fixed GPS receiver. The Doppler radars measure the relative velocities between the radars and the scene, as well as the scene'"'"'s electromagnetic reflectivity, while the video camera records the motion of the camera and the optical property of the scene. The correct registration of the Doppler radars and the camera is established by finding the intersections of the moving Doppler radar motion vectors with the image plane of the video camera. The scene features in the first frame are determined by Doppler circle intersections. The correspondences of the features in the next two frames are established by a feature matching operation.

Claims

1. An imaging system to generate an image of a scene, comprising:

a first movable radar to generate a first radar motion ray;

a second movable radar to generate a second radar motion ray;

a third fixed radar to generate a third radar direction ray;

a stationary video camera to receive data from the intersection of the first radar motion ray and the second radar motion ray,

wherein said first radar motion ray and said second radar motion ray move with respect to the stationary video camera.

2. An imaging system to generate an image of a scene as in claim 1, wherein the second radar is a second Doppler radar.

3. An imaging system to generate an image of a scene as in claim 1, wherein the third fixed radar is a third Doppler radar.

4. An imaging system to generate an image of a scene as in claim 1, wherein the image system includes a sensor apparatus including a global positioning system receiver.

5. An imaging system to generate an image of a scene, comprising:

a first movable radar to generate a first radar motion ray;

a second movable radar to generate a second radar motion ray;

a third fixed radar to generate a third radar direction ray;

a stationary video camera to receive data from the intersection of the first radar motion ray and the second radar motion ray, wherein the imaging system generates a first Doppler difference based upon the difference between the first radar motion ray and the third radar direction ray.

6. An imaging system to generate an image of a scene as in claim 5, wherein the imaging system generates a second Doppler difference based upon the difference between the second radar motion ray and the third radar direction ray.

7. An imaging system to generate an image of a scene as in claim 6, wherein the imaging system generates a second cone angle and a second circle based upon the second Doppler difference.

8. An imaging system to generate an image of a scene as in claim 7, wherein the imaging system generates a feature point based upon the first and second cone angles and the first and second circles.

9. An imaging system to generate an image of a scene as in claim 5, wherein the imaging system generates a first cone angle and a first circle based upon the first Doppler difference.

10. An imaging system to generate an image of a scene as in claim 9, wherein the imaging system generates a Doppler ratio based upon the first and second Doppler differences.

11. An imaging system to generate an image of a scene, comprising:

a first movable radar to generate a first radar motion ray;

a second movable radar to generate a second radar motion ray;

a third fixed radar to generate a third radar direction ray;

a stationary video camera to receive data from the intersection of the first radar motion ray and the second radar motion ray, wherein the imaging system generates a first Doppler difference based upon the difference between the first radar motion ray and the third radar direction ray, a second Doppler difference based upon the difference between the second radar motion ray and the third radar direction ray, generates a Doppler ratio based upon the first and second Doppler differences, a first cone angle and a first circle based upon the first Doppler difference, a second cone angle and a second circle based upon the second Doppler difference, and generates a feature point based upon the first and second cone angles and the first and second circles.

12. An imaging system to generate an image of a scene as in claim 11, wherein the imaging system generates a 3D line equation at each frame.

13. An imaging system to generate an image of a scene as in claim 11, wherein the imaging system generates a 3D scene point from three 3D lines.

14. An imaging system to generate an image of a scene, comprising:

a first movable radar to generate a first radar motion ray;

a second movable radar to generate a second radar motion ray;

a third fixed radar to generate a third radar direction ray;

a stationary video camera to receive data from the intersection of the first radar motion ray and the second radar motion ray, wherein the first radar is a first Doppler radar.

15. An imaging system adapted for registration, comprising:

a first movable radar to generate a first radar motion ray;

a second movable radar to generate a second radar motion ray;

a third fixed radar to generate a third radar direction ray;

a stationary video camera to define an virtual image plane, wherein the first radar motion ray and the second radar motion ray register with the virtual image plane of the video camera,

wherein the first radar motion ray and the second radar motion ray moves with respect to the stationary video camera.

16. An imaging system adapted for registration as in claim 15, wherein the first movable radar is a first movable Doppler radar.

17. An imaging system adapted for registration as in claim 15, wherein the second movable radar is a second movable Doppler radar.

18. An imaging system adapted for registration as in claim 15, wherein the third fixed radar is a third fixed Doppler radar.