System, method, and computer program product providing three-dimensional visualization of ground penetrating radar data

• US 7,675,454 B2
• Filed: 09/07/2007
• Issued: 03/09/2010
• Est. Priority Date: 09/07/2007
• Status: Active Grant

• Current Assignee: NIITEK, Inc.
• Original Assignee: NIITEK, Inc.
• Inventors: Patrikar, Ajay, Lavedas, Steven, Hibbard, Mark
• Primary Examiner(s): Sotomayor; John B
• Application Number:
  US11/852,030
• Publication Number:
  US 20090295617A1
• Time in Patent Office: 914 Days
• Field of Search: 342/22, 342/27, 342/176, 342179-183, 342/185, 342/195, 342/197
• US Class Current: 342/22
• CPC Class Codes: G01S 13/885 for ground probing prospecting or detecting using electromagnetic waves G01V3/12
• CPC Class Codes: G01S 7/20 Stereoscopic displays; Three-dimensional displays; Pseudo-three-dimensional displays

Abstract

A system for analyzing and displaying radar information comprises: a transmit and receive unit operable to transmit radar signals to a survey volume and to receive radar returned radar signals, a processing unit operable to: receive radar data from the returned radar signals, reduce the data into depth bins, each with a score based on received signal strength, create connections among depth bins based on respective scores, and to eliminate ones of the depth bins that do not meet a threshold number of connections, the system further comprising a display unit operable to create a display of at least a subset of the depth bins that are not eliminated by the processing unit.

Claims

1. A method for displaying radar images, said method comprising:

receiving a first scan that includes a plurality of channels of data over a time period, wherein each of said channels includes a plurality of samples corresponding to a portion of a surveyed volume;

reducing the number of samples in said scan by aggregating every N number of samples in a channel into a depth bin, thereby creating a plurality of depth bins, wherein N is a positive integer;

scoring said depth bins according to return strength;

creating mathematical connections among the depth bins based on said return strength, wherein depth bins with stronger returns are assigned a greater radial distance in which to connect to nearby depth bins;

for each of said depth bins, totaling connections both to and from other depth bins;

eliminating those depth bins that do not meet a threshold number of connections, thereby creating a reduced scan; and

displaying data from said reduced scan.

2. The method of claim 1 further comprising:

receiving subsequent scans, and for each of said subsequent scans;

creating additional depth bins;

creating mathematical connections among the depth bins in said first scan and nearby scans; and

eliminating those depth bins that do not meet a threshold number of connections, thereby creating a reduced scan for each of said subsequent scans.

3. The method of claim 1 wherein creating mathematical connections comprises:

for each bin that has one or more potential connections to bins in one or more subsequent scans, storing its state in a delay file and creating connections from said potential connections after depth bins of said subsequent scans are created.

4. The method of claim 1 further comprising:

changing said threshold number of connections based on data gathered from an independent process analyzing said scan.

5. The method of claim 4 wherein said changing said threshold number comprises:

increasing said threshold when said independent process ascertains that some depth bins show decreasing deviation; and

decreasing said threshold when said independent process ascertains that some depth bins show increasing deviation.

6. The method of claim 5 wherein said independent process comprises:

an algorithm for creating a Two-Dimensional (2D) map view of said surveyed volume.

7. The method of claim 1 wherein said displaying comprises:

generating a real-time, Three-Dimensional (3D) view of said surveyed volume and depth.

8. The method of claim 1 wherein said data is data from a Ground Penetrating Radar (GPR) system.

9. The method of claim 1 wherein said displaying said data comprises:

generating a real-time display of a current scan as a cross-track B-scan; and

generating a down-track B-scan that includes selected channels from past scans;

projecting said cross-track B-scan and said down-track B-scan so that they appear in planes orthogonal to each other; and

using said data from said reduced scan and from said past scans, reduced in the same manner as said first scan, generating a display of the data from said reduced scans in Three-Dimensional (3D) positions in relation to corresponding areas of said down-track B-scan.

10. The method of claim 9 wherein generating said down-track B-scan comprises:

selecting a channel from each of said scans as said scans are generated, wherein said selecting includes identifying a channel with a relatively strong depth bin in a current scan and using a sliding algorithm to select a channel that lies between said identified channel and a channel identified in a previous scan.

11. The method of claim 9 further comprising:

providing a visual indicator to said display of the data from said reduced scans, said visual indicator drawing attention to depth bins with relatively high relevance, said visual indicator produced based upon operation of an independent algorithm that identifies items of interest.

12. The method of claim 1 further comprising:

before creating said mathematical connections, eliminating ones of said depth bins that fail to reach a return strength score threshold.

13. A system for analyzing and displaying radar information, said system comprising:

a transmit and receive unit operable to transmit radar signals to a survey volume and to receive returned radar signals;

a processing unit operable to;

receive radar data from said returned radar signals;

reduce said data into depth bins, each with a score based on received signal strength;

create connections among depth bins based on respective scores; and

eliminate ones of said depth bins that do not meet a threshold number of connections; and

a display unit operable to create a Three-Dimensional (3D) display of at least a subset of said depth bins that are not eliminated by said processing unit.

14. The system of claim 13, wherein said 3D display includes a cross-track B-scan display of a current scan.

15. The system of claim 14 wherein said 3D display further includes a down-track B-scan display of channels of past scans, each of said channels selected based, at least in part, on return signal strength.

16. The system of claim 15, wherein said down-track B-scan display and said cross-track B-scan display are arranged in orthogonal planes to create a portion of a rectangular prism, and wherein said data bins are displayed within said rectangular prism.

17. The system of claim 13 wherein a visual indicator is further provided to said 3D display to highlight said depth bins that were not eliminated.

18. The system of claim 13, wherein said system is integrated into a vehicle to perform a radar survey of a portion of the ground.

19. A computer program product having a computer readable medium having computer program logic recorded thereon for processing radar information, said computer program product comprising:

(a) code, when executed by a computer, receiving digital data representing returned radar signals;

(b) code, when executed by a computer, creating depth bins from said digital data and scoring each of said depth bins based on returned signal strength;

(c) code, when executed by a computer, creating relationships among said depth bins represented by connections therebetween, said connections based on said scoring;

(d) code, when executed by a computer, eliminating ones of said depth bins based on said connections; and

(e) code, when executed by a computer, displaying ones of said depth bins that are not eliminated.

20. The computer program product of claim 19 wherein said code eliminating ones of said depth bins further comprises:

code, when executed by a computer, receiving data from an independent radar algorithm and using said data received from said algorithm to adjust a threshold number of connections; and

code, when executed by a computer, comparing scores of each of depth bins to said threshold number of connections.

21. A computer program product having a computer readable medium having computer program logic recorded thereon for displaying radar information, said computer program product comprising:

(a) code, when executed by a computer, receiving radar data representing scans of a surveyed volume as said scans are generated; and

(b) code, when executed by a computer, rendering a down-track B-scan display including portions of previous scans;

wherein said rendering code includes;

code, when executed by a computer, selecting a channel from each of said scans as said scans are generated, wherein said selecting includes identifying a channel with a relatively strong depth bin in a current scan and using a sliding algorithm to select a channel that lies between said identified channel and a channel identified in a previous scan.

22. The computer program product of claim 21 further comprising:

code, when executed by a computer, generating a real-time display of a current scan as a cross-track B-scan; and

code, when executed by a computer, projecting said cross-track B-scan and said down-track B-scan so that they appear as orthogonal of a portion of a rectangular prism.