Method of detecting a scatterer in a structure, a radar system and a computer program product

• US 9,851,439 B2
• Filed: 02/22/2010
• Issued: 12/26/2017
• Est. Priority Date: 02/20/2009
• Status: Active Grant

• Current Assignee: Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno
• Original Assignee: Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno
• Inventors: Smits, Felix Maria Antonius, de Wit, Jacobus Johannes Maria, van Rossum, Wilhelmus Lambertus
• Primary Examiner(s): McGue, Frank J
• Application Number:
  US13/145,127
• Publication Number:
  US 20120105268A1
• Time in Patent Office: 2,864 Days
• Field of Search: 342 22
• CPC Class Codes: G01S 13/888 through wall detection
• CPC Class Codes: G01S 13/89 for mapping or imaging
• CPC Class Codes: G01S 7/025 involving the transmission of linearly polarised waves

Abstract

The invention relates to a method of detecting a scatterer in a structure, such as a building structure. The method comprises the steps of transmitting from one or a multiple number of positions exterior to a structure, a wall probing radar signal towards the structure. The method also comprises the step of receiving, at one or a multiple number of positions exterior to the structure, signals that have been reflected by scatterers in the structure. Further, the method comprises the step of filtering, from the received signals, reflection information of a specific scatterer at a specific position. In addition, the method comprises the step of identifying a geometry of the specific scatterer, based on the reflection information. The filtering step comprises applying a phase change algorithm corresponding to a specific scatterer type.

Claims

1. A method of mapping a scatterer in a structure, comprising the steps of:

moving a platform along the structure;

transmitting, while the platform is continuously moving along the structure, from one or a multiple number of positions on the moving platform exterior to a structure, a wall probing radar signal towards the structure;

receiving, while the platform is continuously moving along the structure, at one or a multiple number of positions on the moving platform exterior to the structure, radar signals that have been reflected by scatterers in the structure;

filtering, from the received signals, reflection information of a specific scatterer at a specific position;

identifying a geometry of the specific scatterer, based on the reflection information,

wherein the filtering step comprises applying a phase change algorithm corresponding to a specific scatterer type, wherein the phase change algorithm uses at least two different measurement positions of the moving platform as the platform is continuously moving to identify and map the specific scatterer; and

mapping the specific scatterer in the structure.

2. The method according to claim 1, wherein the filtering step comprises at least one of applying a linear phase change algorithm and a quadratic phase change algorithm.

3. The method according to claim 1, further comprising constructing a three-dimensional map of a building structure based on the identified scatterer geometry.

4. The method according claim 1, wherein the identified scatterer geometry is formed from at least one of a flat surface, a curved surface, a single intersection of flat or curved surfaces or multiple intersections of flat or curved surfaces.

5. The method according to claim 1, wherein the filtering step comprises applying at least one of a far-field beam forming technique and a near-field beam focusing technique.

6. The method according to claim 1, wherein the wall probing radar signal is a frequency modulated continuous wave (FMCW).

7. The method according to claim 1, further comprising determining an orientation of the specific scatterer.

8. The method according to claim 1, further comprising constructing a three-dimensional building map by linking identified geometries of scatterers.

9. The method according to claim 1, further including transmitting and receiving radar signals having different polarization types.

10. The method according to claim 1, further comprising the step of observing signal amplitude and that a signal of a first polarization type changes its sign while a signal of a second polarization maintains its sign as a function of the angle with respect to a reflection section of the scatterer for identification of a dihedral corner and determination of material properties of the scatterer.

11. The method according to claim 1, wherein the identified scatterer geometry comprises at least one of a substantially planar wall, a substantially dihedral corner in a substantially horizontal direction, a dihedral corner in a substantially vertical direction and a trihedral corner.

12. A radar system for mapping a scatterer in a structure, comprising:

a transceiver module on a movable platform moving along the structure and being arranged for;

transmitting, while the platform is continuously moving along the structure, from one or a multiple number of positions on the moving platform exterior to a structure, a wall probing radar signal towards the structure;

receiving, while the platform is continuously moving along the structure, at one or a multiple number of positions on the moving platform exterior to the structure, radar signals that have been reflected by scatterers in the structure; and

a processor arranged for;

filtering, from the received signals, reflection information of a specific scatterer at a specific position;

identifying a geometry of the specific scatterer, based on the reflection information,

wherein the filtering step comprises applying a phase change algorithm corresponding to a specific scatterer type, wherein the phase change algorithm uses at least two different measurement positions of the moving platform as the platform is continuously moving to identify the specific scatterer; and

mapping the specific scatterer in the structure.

13. The system according to claim 12, wherein the transceiver module comprises a multiple number of transmitters and receivers arranged in a linear array.

14. The system according to claim 13, wherein the linear array is slightly tilted with respect to the vertical.

15. The system according to claim 13 wherein the linear array is in a multiple input multiple output (MIMO) configuration.

16. An article of manufacture comprising a non-transitory computer usable medium having encoded thereon a set of instructions executable by a computer system to perform one or more operations for mapping a scatterer in a structure, the set of instructions comprising:

filtering reflection information of a specific scatterer at a specific position, from signals that have been received, at one or a multiple number of positions on a moving platform exterior to a structure, while the platform is continuously moving along the structure, the received radar signals propagating from scatterers after a wall probing radar signal has been transmitted, from one or a multiple number of positions on a moving platform exterior to a structure, towards the structure, while the platform is continuously moving along the structure;

identifying a geometry of the specific scatterer, based on the reflection information,

wherein the filtering step comprises applying a phase change algorithm corresponding to a specific scatterer type and at least two different measurement positions of the moving platform while the platform is continuously moving along the structure; and

mapping the specific scatterer in the structure.