Apparatus and method for spatial encoding of a search space

• US 7,773,204 B1
• Filed: 02/28/2008
• Issued: 08/10/2010
• Est. Priority Date: 07/20/2006
• Status: Expired due to Fees

• Current Assignee: the united states of america as represented by the secretary of the navy
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Nelson, Robert Sigurd
• Primary Examiner(s): Tarcza; Thomas H
• Assistant Examiner(s): Ratcliffe; Luke D
• Application Number:
  US12/039,531
• Time in Patent Office: 894 Days
• Field of Search: 356 301- 285
• US Class Current: 356/5.02
• CPC Class Codes: G01S 13/48 using multiple beams at emission or reception
• CPC Class Codes: G01S 13/52 Discriminating between fixed and moving objects or between objects moving at different speeds
• CPC Class Codes: G01S 13/74 Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems
• CPC Class Codes: G01S 13/862 Combination of radar systems with sonar systems
• CPC Class Codes: G01S 13/867 Combination of radar systems with cameras
• CPC Class Codes: G01S 15/46 Indirect determination of position data
• CPC Class Codes: G01S 15/89 for mapping or imaging
• CPC Class Codes: G01S 17/46 Indirect determination of position data
• CPC Class Codes: G01S 7/403 in azimuth, i.e. in the horizontal plane
• CPC Class Codes: G01S 7/4034 in elevation, i.e. in the vertical plane
• CPC Class Codes: G01S 7/4056 specially adapted to FMCW
• CPC Class Codes: G01S 7/4091 during normal radar operation
• CPC Class Codes: G01S 7/4972 Alignment of sensor

Abstract

Spatial encoding of a search space is achieved by an array of radiation or acoustic energy detectors receiving data from at least one radiation or energy source. At least one radiation source capable of providing a predetermined type of radiation is used. The radiation may be in the form of a plurality of beams arrayed along at least one directional axis, and arranged in successive alignment to exhibit a directional component. The directional component is characterized by a frequency variance between successive beams in accordance with direction and disposed so radiation therefrom propagates within the search space. At least one radiation detector capable of detecting the radiation is provided, and is disposed to detect at least that type of radiation.

Claims

1. An apparatus for spatial encoding of a search space comprising:

at least one radiation source capable of providing a predetermined type of radiation in the form of a plurality of beams arrayed along at least one directional axis, the beams arranged in successive alignment to exhibit a directional component characterized by a frequency variance between successive beams in accordance with direction and disposed so radiation therefrom propagates within the search space;

at least one radiation detector capable of detecting the predetermined type of radiation and disposed to detect at least the predetermined type of radiation; and

at least one additional and separate radiation detector provided to measure background noise signals by detecting a non-uniform index of refraction distribution.

2. The apparatus of claim 1, further comprising:

the radiation source providing at least one of electromagnetic (EM) radiation, ionizing radiation, and acoustic radiation.

3. The apparatus of claim 1, wherein the radiation source provides an encoded waveform comprising one of wavelength, time of flight (TOF), waveform, polarization and phase.

4. The apparatus of claim 3, further comprising the encoded waveform provided as a spatial grid formed by said plurality of beams arrayed along the directional axis.

5. The apparatus of claim 4, wherein the spatial grid is a remote source spatial grid.

6. The apparatus of claim 4, wherein the spatial grid is a local source spatial grid.

7. The apparatus of claim 1, wherein at least one radiation source is mobile.

8. The apparatus of claim 1, further comprising at least one reference object disposed for calibrating the search space.

9. The apparatus of claim 1,

wherein the background noise signals are generated by natural features including snapping shrimp.

10. The apparatus of claim 1, further comprising:

at least one radiation detector provided to measure background noise signals;

wherein the background noise signals are generated by an artificial signal generator.

11. The apparatus of claim 1, further comprising:

at least one radiation detector provided to measure background noise signals;

wherein the background noise signals are generated by an artificial signal generator simulating a natural feature.

12. The apparatus of claim 1, further comprising:

a second radiation source capable of providing a predetermined type of radiation in the form of a plurality of beams arrayed along at least one directional axis, the beams arranged in successive alignment to exhibit a directional component characterized by a frequency variance between successive beams in accordance with direction and disposed so radiation therefrom propagates within the search space, wherein the beams provided by the radiation source and the second radiation source are configured to create a grid of coherent crossed beams in the search space.

13. A method for detecting and tracking an object within a search space, the method comprising:

providing, from at least one radiation source, a predetermined type of radiation in the form of a plurality of beams arrayed along at least one directional axis, the beams arranged in successive alignment to exhibit a directional component characterized by a frequency variance between successive beams in accordance with direction and disposed so radiation therefrom propagates within the search space;

using at least one radiation detector to detect the predetermined type of radiation;

using a second radiation detector to measure background noise signals by detecting non-uniform index of refraction distribution; and

using a natural feature as background noise signals.

14. The method of claim 13, further comprising providing at least one of EM radiation, ionizing radiation, and acoustic radiation.

15. The method of claim 13, further comprising causing the radiation to propagate within the search space, so as to allow detection by at least one radiation detector associated with the at least one radiation source and disposed to detect at least one of EM radiation, ionizing radiation, and acoustic radiation.

16. The method of claim 15, further comprising providing the encoded waveform as a spatial grid.

17. The method of claim 13, further comprising:

using an artificial signal generator to generate the background noise signals such that the background noise signals at least partially simulate a natural feature.

18. The method of claim 13, further comprising:

using a second radiation source for providing a predetermined type of radiation in the form of a plurality of beams arrayed along at least one directional axis, the beams arranged in successive alignment to exhibit a directional component characterized by a frequency variance between successive beams in accordance with direction and disposed so radiation therefrom propagates within the search space, wherein the beams provided by the radiation source and the second radiation source are configured to create a grid of coherent crossed beams in the search space.