System and method for time reversal situational awareness

Patent metadata

Field	Value
Publication number	US-10168599-B2
Application number	US-201615006244-A
Country	US
Kind code	B2
Filing date	Jan 26, 2016
Priority date	Jan 26, 2016
Publication date	Jan 1, 2019
Grant date	Jan 1, 2019

Abstract

A system and method are disclosed for providing time reversal situational awareness. An input filter receives an input signal at a first frequency and a pump signal at a second frequency and blocks signals at a third predetermined frequency. A non-linear medium performs a second order operation or a third order operation on the filtered input signal and the filtered pump signal to produce an output signal at the third frequency, the third frequency lower than the first frequency and the second frequency. An output filter is coupled to receive the output signal from the non-linear medium and blocks signals at the first frequency and at the second frequency such that a filtered output signal is generated that is a phase conjugate signal which provides time reversal situational awareness.

First claim

What is claimed is:

1. A system for providing time reversal situational awareness, the system comprising:
an input filter for receiving an input signal at a first frequency and a pump signal at a second frequency, the input filter configured to block signals at a third frequency, wherein the input signal comprises an image of an object;
a single non-linear medium directly coupled to an output of the input filter, the single non-linear medium configured to receive the input signal and the pump signal from the input filter, the single non-linear medium further configured to perform a second order operation or a third order operation on the input signal and the pump signal to generate an output signal at the third frequency, the third frequency lower than the first frequency and the second frequency, wherein the output signal includes a phase conjugate signal;
an output filter coupled to receive the output signal directly from the single non-linear medium, the output filter configured to block signals at the first frequency and at the second frequency and to generate a filtered output signal that includes only the phase conjugate signal; and
calculation circuitry configured to determine, based on the phase conjugate signal, behavior of the object prior to receipt of the input signal.

2. The system of claim 1 , wherein the single non-linear medium is configured to perform a second order operation.

3. The system of claim 2 , where the second order operation is a difference frequency generation operation.

4. The system of claim 1 , wherein the single non-linear medium is configured to perform a third order operation.

5. The system of claim 4 , wherein the third order operation is a stimulated Raman scattering operation.

6. The system of claim 4 , wherein the third order operation is a stimulated Brillouin scattering operation.

7. The system of claim 4 , wherein the third order operation is a phase conjugation operation.

8. The system of claim 1 , wherein the filtered output signal is used to identify information about the object prior to receipt of the input signal.

9. The system of claim 1 , wherein the behavior of the object corresponds to movement of the object prior to receipt of the input signal.

10. The system of claim 1 , wherein the input filter comprises:
an intensity control element;
a polarization control element coupled to the intensity control element; and
a frequency control element coupled to the polarization control element.

11. The system of claim 10 , wherein the intensity control element comprises one or more lenses, wherein the polarization control element comprises a polarizer and a waveplate, and wherein the frequency control element comprises an optical filter.

12. The system of claim 1 , wherein the single non-linear medium comprises Potassium Titanyl Phosphate, Potassium DiHydrogen Phosphate, or Potassium Titanyl Arsenate.

13. The system of claim 1 , wherein the single non-linear medium comprises Lithium Triborate or Beta Barium Borate.

14. A method for providing time reversal situational awareness, the method comprising:
filtering an input signal at a first frequency and a pump signal at a second frequency to block signals at a third frequency, wherein the input signal comprises an image of an object;
performing, at a single non-linear medium, a second order operation or a third order operation directly on the input signal and the pump signal to generate an output signal at the third frequency, the third frequency lower than the first frequency and the second frequency, wherein the output signal includes a phase conjugate signal;
filtering the output signal received directly from the single non-linear medium to block signals at the first frequency and at the second frequency and to generate a filtered output signal that includes only the phase conjugate signal; and
determining, based on the phase conjugate signal, behavior of the object prior to receipt of the input signal.

15. The method of claim 14 , wherein the single non-linear medium performs a second order operation.

16. The method of claim 15 , where the second order operation is a difference frequency generation operation.

17. The method of claim 14 , wherein the single non-linear medium performs a third order operation.

18. The method of claim 17 , wherein the third order operation is a stimulated Raman scattering operation or a stimulated Brillouin scattering operation.

19. The method of claim 17 , wherein the third order operation is a phase conjugation operation.

20. The method of claim 14 , further comprising identifying information about the object prior to receipt of the input signal based on the filtered output signal.

Assignees

• Boeing Co

Inventors

• Hunt Jeffrey H

Classifications

• G02F1/353 Primary

  Frequency conversion, i.e. wherein a light beam is generated with frequency components different from those of the incident light beams · CPC title

• G02F1/3501

  Constructional details or arrangements of non-linear optical devices, e.g. shape of non-linear crystals · CPC title

• G02F2001/3503

  Physics · mapped topic

• G01S7/4816

  of receivers alone · CPC title

• G02F1/3534

  Three-wave interaction, e.g. sum-difference frequency generation (G02F1/3532 takes precedence) · CPC title