Synchronized infrared beacon / infrared detection system

Patent metadata

Field	Value
Publication number	US-9887775-B2
Application number	US-201514714617-A
Country	US
Kind code	B2
Filing date	May 18, 2015
Priority date	Nov 16, 2012
Publication date	Feb 6, 2018
Grant date	Feb 6, 2018

Abstract

A synchronized infrared beacon/infrared detector system. The system may include (A) an infrared beacon module configured to generate a time-varying encoded infrared signal, (B) an infrared detector module configured to capture the encoded infrared signal generated by the beacon module, (C) a synchronizer configured to generate a synchronization signal that controls timing of the beacon module and the detector module, and (D) a processor, in communication with the detector module, configured to analyze the infrared signal captured by the detector module. The infrared signal may be modulated at frequencies undetectable by human vision. The synchronizer signal may be produced independent of the capture of, and without input from, the infrared signal.

First claim

We claim:

1. A synchronized infrared beacon/infrared detection system, comprising:
an infrared beacon module configured to generate a time-varying encoded infrared signal;
an infrared detector module configured to capture the infrared signal;
wherein the beacon module and/or the detector module are configured to generate a synchronization signal and to provide the synchronization signal directly between the beacon module and the detector module to control the timing between the beacon module and the detector module; and
a processor configured to analyze the infrared signal captured by the detector module, wherein the processor is configured to recognize and decode the infrared signal to provide data communication directly between the beacon module and the detector module when synchronization based on the synchronization signal is not established between the beacon module and the detector module.

2. The system of claim 1 , wherein the synchronization signal is generated independent of the capture of the infrared signal.

3. The system of claim 1 , wherein the infrared detector module comprises a first synchronizer configured to synchronize the infrared detector module based on the synchronization signal to capture the infrared signal when the infrared beacon module is selectively generating the infrared signal.

4. The system of claim 1 , wherein the detector module further includes a non-imaging detector configured to capture the infrared signal.

5. The system of claim 1 , wherein the infrared signal is characterized by a frequency that is above a human flicker fusion threshold.

6. The system of claim 1 , wherein the infrared signal is in a MWIR and/or a LWIR waveband.

7. The system of claim 1 , wherein the infrared detector module comprises a first synchronizer, the infrared beacon module comprises a second synchronizer, and wherein the processor is further configured to perform a temporal and/or spatial signal pattern recognition to recognize the infrared signal and synchronize to it.

8. The system of claim 1 , wherein the infrared signal is characterized by a defined frequency that is a fraction of, or an integer multiple of, a frame rate of the detector.

9. The system of claim 1 , wherein the infrared signal is at least partially non-periodic, and wherein a non-periodic infrared signal is encoded to provide data communication.

10. The system of claim 1 , wherein the detector module has a frame rate at which it acquires images, and wherein the frame rate can be adjusted to match, or be proportional to, a frequency of the infrared signal.

11. The system of claim 1 , wherein the infrared signal appears as a continuous signal unless the infrared beacon and infrared detector modules are synchronized.

12. The system of claim 1 , wherein the detector module includes a filter configured to filter out signals having a flashing frequency profile insufficiently correlated to a predetermined signature.

13. The system of claim 1 , wherein the processor is configured to extract a flashing frequency profile from the infrared signal, compare the extracted profile to a desired profile, and transmit an activation signal to the detector module only if the extracted profile matches the desired profile, independent of the synchronization signal.

14. The system of claim 1 , wherein the infrared beacon module only generates an infrared signal after being triggered by the synchronization signal.

15. The system of claim 1 , further comprising a sensor configured to provide information to the beacon module that can be encoded in the infrared signal and thereby transmitted to the detector module.

16. The system of claim 1 , further comprising a plurality of infrared beacon modules, each configured to generate a distinct time-varying encoded infrared signal, wherein the infrared detector module and the processor are configured to function with each beacon module.

17. The system of claim 16 , wherein there is a phase delay between the infrared detector module and at least some of the plurality of infrared beacon modules.

18. A method, comprising:
generating an encoded infrared signal comprising an emission of radiation using a beacon module;
detecting the signal using a detector module;
synchronizing between the beacon and detector modules, using a synchronization signal provided directly between the beacon module and the detector module, wherein the synchronization signal is provided from the beacon module to the detector module and/or from the detector module to the beacon module, so that there is a defined and predetermined relationship between the emission of radiation by the beacon module and the detection of the radiation by the detector module;
tracking the beacon module by extracting a flashing frequency profile from the infrared signal;
comparing the extracted profile to a desired profile; and
transmitting an activation signal to the detector module only if the extracted profile matches the desired profile, independent of the synchronization signal.

19. The method of claim 18 , further comprising providing communication between the beacon module and the detector module by analyzing, recognizing, and decoding the infrared signal to provide data communication when synchronization is not established.

20. A method, comprising:
synchronizing between a beacon module and a detector module, using a synchronization signal provided directly between the beacon module and the detector module, wherein the synchronization signal is provided from the beacon module to the detector module and/or from the detector module to the beacon module;
generating an encoded infrared signal using the beacon module;
detecting the infrared signal using the detector module; and
providing communication directly between the beacon module and the detector module via a processor, wherein the processor analyzes, recognizes, and decodes the beacon signal to provide data communication when synchronization is not established between the beacon module and the detector module.

21. The method of claim 20 , further comprising tracking the beacon module by extracting a flashing frequency profile from the infrared signal, comparing the extracted profile to a desired profile, and transmitting an activation signal to the detector module only if the extracted profile matches the desired profile, independent of the synchronization signal.

22. The method of claim 20 , further comprising synchronizing between the beacon and detector modules, using the synchronization signal provided directly between the beacon module and the detector module, wherein the synchronization signal is provided from the beacon module to the detector module and/or from the detector module to the beacon module, so that there is a defined and predetermined relationship between emission of radiation by the beacon module and detection of the radiation by the detector module.

Assignees

• Flir Systems

Inventors

• Puscasu Irina
• Poirier Bruce Allen

Classifications

• G01S17/74

  Systems using reradiation of electromagnetic waves other than radio waves, e.g. IFF, i.e. identification of friend or foe · CPC title

• F41J5/08

  Infrared hit-indicating systems · CPC title

• F41H13/00

  Means of attack or defence not otherwise provided for {(details of radar or sonar systems G01S7/00)} · CPC title

• F41H1/00 Primary

  Personal protection gear (shields for personal use F41H5/08; {footwear for use in minefields A43B3/0026}; for protection against chemical warfare A62B) · CPC title

• H04B10/11 Primary

  Arrangements specific to free-space transmission, i.e. transmission through air or vacuum · CPC title