ELECTROMAGNETIC (EM) POWER DENSITY AND FIELD CHARACTERIZATION TECHNIQUE

• US 20140043487A1
• Filed: 08/15/2013
• Published: 02/13/2014
• Est. Priority Date: 07/30/2010
• Status: Active Grant

• 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: Marandos, Peter, Patterson, Grady, Leeson, Kenneth
• Granted Patent: US 9,325,914 B2
• Time in Patent Office: Days
• US Class Current: 348/164
• CPC Class Codes: G01J 2005/0077 Imaging
• CPC Class Codes: G01J 5/0003 for sensing the radiant heat transfer of samples, e.g. emittance meter
• CPC Class Codes: G01J 5/485 Temperature profile
• CPC Class Codes: G01J 5/58 using absorption; using extinction effect
• CPC Class Codes: H04N 23/20 for generating image signals from infrared radiation only
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

An apparatus and method for characterization of a directed beam of electromagnetic radiation is provided. An exemplary embodiment of the invention can include an apparatus and measuring technique method which uses a model for blackbody radiation that includes consideration all the degrees of freedom due to translation, vibration, and rotation of molecules or atoms that make up the absorber and a heat transfer term which averages the behavior of all the atoms of the material as a function of temperature. This apparatus and method provides an advantage of increased accuracy, substantial reductions of time required for processing, simplification of measuring processes, and reduction required equipment.

Claims

1. An electromagnetic field characterization apparatus comprising:

an electromagnetic source adapted to emit an electromagnetic field;

an electromagnetic absorption material adapted to receive said electromagnetic field;

a plurality of temperature sensors adapted to orient on said electromagnetic absorption material and output a plurality of temperature sensor data;

a plurality of processing sequences comprising;

a first processing sequence adapted to receive said plurality of temperature sensor data and store a plurality of temperature sensor data frames created based on said plurality of temperature sensor data in a first data structure, said temperature sensor data frames comprise a plurality of temperature data associated with some or all of said temperature sensors stored at different points of time;

a second processing sequence adapted to select at least two of said temperature sensor data frames based at least on a first and second temperature data parameter determined based on comparisons of all said temperature sensor data frames to find an initial state and a final state associated with temperature changes in said electromagnetic absorption material, said at least two selected temperature sensor data frames comprise an initial and final temperature sensor data frame, said second processing sequence is further adapted to determine a time differential data for every two of said selected at least two temperature sensor data frames, said second processing sequence is further adapted to store said selected at least two temperature sensor data frames and said time differential data in a second data structure;

a third processing sequence adapted to determine a plurality of power density data associated with some or all of said plurality of temperature data in said initial and final temperature sensor data frames, said plurality of power density data is determined based on data stored in said second data structure, absorption attributes associated with said electromagnetic absorption material, a plurality of blackbody radiation attributes associated with said electromagnetic absorption material comprising degrees of freedom attributes, and a plurality of cooling attributes associated with a cooling medium in proximity to said electromagnetic absorption material, said second processing sequence further outputs and stores a power density image map in a third data structure, said power density image map comprising a power density data associated with all or a portion of said plurality of temperature sensors; and

a fourth processing sequence adapted to produce a graphical or data output of said power density image map.

2. An electromagnetic field characterization apparatus as in claim 1, further comprising providing a temperature control mechanism which provides cooling to said electromagnetic absorption material.

3. An electromagnetic field characterization apparatus as in claim 2, wherein said temperature control mechanism is a circulation fan adapted to ensure approximately uniform heat transfer associated with said electromagnetic absorption material;

4. An electromagnetic field characterization apparatus as in claim 1, wherein said electromagnetic source is a radio frequency source coupled to an electromagnetic field radiating structure.

5. An electromagnetic field characterization apparatus as in claim 1, wherein said plurality of temperature sensors comprises one or more infrared image sensing systems.

6. An electromagnetic field characterization apparatus as in claim 1, wherein said first and second temperature data parameters are determined based on a determination of a high and low temperature value associated with a first and second approximate temperature equilibrium defined as a case where temperature change in the electromagnetic absorption material does not exceed a predetermined value over a predetermined period of time.

7. An electromagnetic field characterization apparatus as in claim 1, wherein said first temperature parameter is a lowest temperature data value and said second temperature parameter is a highest temperature value.

8. An electromagnetic field characterization apparatus as in claim 1, further comprising a mechanism adapted to move said electromagnetic source or the electromagnetic absorption material in relation to each other in order to manipulate either said electromagnetic field which is being measured or manipulate the electromagnetic absorption material to move it through the electromagnetic field which is being measured in order to produce a plurality of power density image maps each representing a different plane measurement of said electromagnetic field or a three-dimensional power density image map.

9. An electromagnetic field characterization apparatus as in claim 1, wherein said first processing sequence further selects additional said temperature sensor data frames in between said initial and final temperature sensor data frames and determines associated time differentials between consecutive said selected additional temperature sensor data frames, wherein said second processing sequence for calculating a power density data further serially calculates power density between each two of said selected temperature sensor data frames then said second processing sequence sums all of the power density data for each two consecutive temperature sensor data frame from said initial frame to said final frame to produce a final power density data.

10. An electromagnetic field characterization apparatus comprising:

an electromagnetic source adapted to emit electromagnetic field;

an electromagnetic absorption material adapted to receive said electromagnetic field;

a plurality of temperature sensors adapted to orient on said electromagnetic absorption material and output a plurality of temperature sensor data frames data, wherein said plurality of temperature sensors comprise a plurality of temperature sensor pixels and said plurality of temperature sensor data frame data each store a temperature data output from each said temperature sensor pixels;

a plurality of processing sequences comprising;

a first processing sequence adapted to select and store an initial and final temperature sensor data frame from said plurality of temperature sensor data frames based on a first and second temperature parameter, said first processing sequence further determines a differential temperature data associated with said initial and final temperature sensor data frames;

a second processing sequence for calculating a power density data associated with all or a portion of said plurality of temperature sensors and said final temperature sensor data frame, said second processing sequence determines said power density data based on a power density per said pixel calculation comprising a peak power density value based on a plurality of calculation elements comprising a coefficient of absorption of the electromagnetic absorption material, a coefficient of transmission of the electromagnetic absorption material, the final temperature of the electromagnetic absorption material, the initial temperature of the electromagnetic absorption material, emissivity of the electromagnetic absorption material, Stefan-Boltzmann constant, a specific heat of at least one heat sink, a volume of the at least one heat sink, a density of the at least one heat sink, a contact area between the electromagnetic absorption material and the at least one heat sink, a time differential between the initial and final temperature sensor data frames, and degrees of freedom of atoms or molecules that comprise the electromagnetic absorption material and a plurality of inputs to said power density per said pixel calculation including said differential temperature data, wherein said calculation is modified based on a particular said electromagnetic absorption material, wherein the modified calculation components are coefficient of absorption of the electromagnetic absorption material, a plurality of degrees of freedom data for atoms or molecules associated with said electromagnetic absorption material, emissivity of blackbody radiation associated with said electromagnetic absorption material, specific heat capacity of the at least one heat sink placed in proximity to said electromagnetic absorption material, density of the at least one heat sink, volume of the at least one heat sink, and area of interface between the at least one heat sink and said electromagnetic absorption material; and

a third processing sequence for producing at least one graphical user interface, said at least one graphical user interface comprises a power density image output produced based on a plurality of ranges of power density values which depicts said power density data, said at least one graphical user interface also is adapted to display one or more said power density data associated with at least one of said plurality of temperature sensors.

11. An electromagnetic field characterization apparatus as in claim 10, further comprising a processing system adapted to process said plurality of processing sequences and produce a plurality of outputs comprising said power density image output.

12. An electromagnetic field characterization apparatus as in claim 10, further comprising providing a temperature control mechanism which provides cooling to said electromagnetic absorption material.

13. An electromagnetic field characterization apparatus as in claim 12, wherein said temperature control mechanism is a circulation fan.

14. An electromagnetic field characterization apparatus as in claim 10, wherein said electromagnetic source is a radio frequency source coupled to an electromagnetic field radiating structure.

15. An electromagnetic field characterization apparatus as in claim 10, wherein said plurality of temperature sensors comprises one or more infrared image sensing apparatus.

16. An electromagnetic field characterization apparatus as in claim 10, wherein said plurality of temperature sensors is a video camera adapted to record infrared or near infrared spectrum energy.

17. An electromagnetic field characterization apparatus as in claim 10, wherein said first temperature parameter is a lowest temperature data value and said second temperature parameter is a highest temperature value.

18. An electromagnetic field characterization apparatus as in claim 10, further comprising a mechanism adapted to move said electromagnetic source or the electromagnetic absorption material relation to each other in order to manipulate either said electromagnetic field which is being measured or manipulate the electromagnetic absorption material to move it through the electromagnetic field which is being measured.

19. An electromagnetic field characterization apparatus as in claim 10, wherein said first processing sequence further selects additional temperature sensor data frames in between said initial and final temperature sensor data frames and determines associated time differentials between consecutive said additional temperature sensor data frames, wherein said second processing sequence for calculating a power density data further serially calculates power density between each two selected temperature sensor data frames then said second processing sequence sums all of the power density data for each two consecutive temperature sensor data frame from said initial frame to said final frame to produce a final power density data.

20. An electromagnetic field characterization apparatus comprising:

an electromagnetic source adapted to produce electromagnetic radiation;

an electromagnetic absorption material adapted and positioned to said electromagnetic radiation;

at least one array of temperature sensors adapted to focus on said electromagnetic absorption material and output a plurality of temperature sensor data frames comprising a plurality of temperature sensor data associated with a single temperature sensor in said array, wherein each said temperature sensor data frame is associated with a different time data value than other said temperature sensor data frames;

a plurality of processing sequences comprising;

a first processing sequence adapted to store said plurality of temperature sensor data frames and store said plurality of temperature sensor data frames in a first data structure;

a second processing sequence adapted to analyze data stored in said first data structure and select an initial temperature sensor data frame and a final temperature sensor data frame, wherein said initial and final temperature sensor data frames are selected from said plurality of sensor data frames stored in said first data structure based on determination of an initial and final temperature data associated with at least two of said plurality of temperature sensor data frames, said second processing sequence further determines a differential time data associated with said initial and final temperature data frames based on a first and second temperature parameter, said second processing sequence further stores said initial and final temperature sensor data frames and said differential time data a second data structure;

a third processing sequence comprises a power density per temperature sensor calculation adapted to calculate a plurality of power density data associated with said final temperature sensor data frames and said time differential data stored in said second data structure, said third processing sequence is further adapted to store said plurality of power density data in a third data structure, each power density data is individually associated with one or more temperature sensors in said at least one array of temperature sensors, wherein said plurality of power density data is calculated based on;

a blackbody radiation calculation based on said electromagnetic radiation associated with said initial and final temperature sensor data frames;

a determination of cooling of said electromagnetic absorption material based on said initial and final temperature sensor data frames and said differential time data;

a coefficient of a blackbody radiation term determined based on at least a plurality of degrees of freedom data each associated with at least one category of atoms or molecules making up said electromagnetic absorption material;

a plurality of constants associated with said electromagnetic absorption material comprising emissivity, Stefan-Boltzmann Constant, specific heat capacity of a cooling medium placed in proximity to said electromagnetic absorption material, density of said cooling medium, volume of said cooling medium, and an area that said cooling medium makes contact with said electromagnetic absorption material; and

a data value determined based on how much of said electromagnetic radiation incident on said electromagnetic absorption material is absorbed by said electromagnetic absorption material;

a fourth processing sequence adapted to produce a plurality of outputs comprising a power density image representation based on said plurality of power density data.

21. An electromagnetic field characterization apparatus as in claim 20, further comprising a processing system adapted to process said plurality of processing sequences and data structures and produce a plurality of said outputs comprising said power density image representation.

22. An electromagnetic field characterization apparatus as in claim 20, wherein said second processing sequence further selects additional temperature sensor data frames in between said initial and final temperature sensor data frames and determines associated time differentials between consecutive said additional temperature sensor data frames, wherein said third processing sequence for calculating a power density per temperature sensor data further serially calculates power density between each two selected temperature sensor data frames then said second processing sequence sums all of the power density data for each two consecutive temperature sensor data frames from said initial frame to said final frame to produce a final said plurality of power density data.

23. An electromagnetic field characterization apparatus as in claim 20, further comprising providing a temperature control mechanism which provides cooling to said electromagnetic absorption material.

24. An electromagnetic field characterization apparatus as in claim 20, wherein said temperature control mechanism is a circulation fan.

25. An electromagnetic field characterization apparatus as in claim 20, wherein said electromagnetic source is a radio frequency source coupled to an electromagnetic field radiating structure.

26. An electromagnetic field characterization apparatus as in claim 20, wherein said plurality of temperature sensors comprises one or more infrared image sensing apparatus.

27. An electromagnetic field characterization apparatus as in claim 20, wherein said first temperature parameter is a lowest temperature data value and said second temperature parameter is a highest temperature value.

28. An electromagnetic field characterization apparatus as in claim 20, further comprising a mechanism adapted to move said electromagnetic source or the electromagnetic absorption material relation to each other in order to manipulate either said electromagnetic field which is being measured or manipulate the electromagnetic absorption material to move it through the electromagnetic field which is being measured.

29. A method of manufacturing an electromagnetic field characterization apparatus comprising:

providing an electromagnetic source adapted to emit an electromagnetic field;

providing an electromagnetic absorption material adapted to receive said electromagnetic field;

providing a plurality of temperature sensors adapted to orient on said electromagnetic absorption material and output a plurality of temperature sensor data;

providing a plurality of processing sequences comprising;

a first processing sequence adapted to receive said plurality of temperature sensor data and store a plurality of temperature sensor data frames created based on said plurality of temperature sensor data in a first data structure, said temperature sensor data frames comprise a plurality of temperature data associated with some or all of said temperature sensors stored at different points of time;

a second processing sequence adapted to select at least two of said temperature sensor data frames based at least on a first and second temperature data parameter determined based on comparisons of all said temperature sensor data frames to find an initial state and a final state associated with temperature changes in said electromagnetic absorption material, said at least two selected temperature sensor data frames comprise an initial and final temperature sensor data frame, said second processing sequence is further adapted to determine a time differential data for every two of said selected at least two temperature sensor data frames, said second processing sequence is further adapted to store said selected at least two temperature sensor data frames and said time differential data in a second data structure;

a third processing sequence adapted to determine a plurality of power density data associated with some or all of said plurality of temperature data in said initial and final temperature sensor data frames, said plurality of power density data is determined based on data stored in said second data structure, absorption attributes associated with said electromagnetic absorption material, a plurality of blackbody radiation attributes associated with said electromagnetic absorption material comprising degrees of freedom attributes, and a plurality of cooling attributes associated with a cooling medium in proximity to said electromagnetic absorption material, said second processing sequence further outputs and stores a power density image map in a third data structure, said power density image map comprising a power density data associated with all or a portion of said plurality of temperature sensors; and

a fourth processing sequence adapted to produce a graphical or data output of said power density image map.

30. A method of manufacturing an electromagnetic field characterization apparatus as in claim 29, further comprising providing a temperature control mechanism which provides cooling to said electromagnetic absorption material.

31. A method of manufacturing an electromagnetic field characterization apparatus as in claim 30, wherein said temperature control mechanism is a circulation fan adapted to ensure approximately uniform heat transfer associated with said electromagnetic absorption material;

32. A method of manufacturing an electromagnetic field characterization apparatus as in claim 29, wherein said electromagnetic source is a radio frequency source coupled to an electromagnetic field radiating structure.

33. A method of manufacturing an electromagnetic field characterization apparatus as in claim 29, wherein said plurality of temperature sensors comprises one or more infrared image sensing systems.

34. A method of manufacturing an electromagnetic field characterization apparatus as in claim 29, wherein said first and second temperature data parameters are determined based on a determination of a high and low temperature value associated with a first and second approximate temperature equilibrium defined as a case where temperature change in the electromagnetic absorption material does not exceed a predetermined value over a predetermined period of time.

35. A method of manufacturing an electromagnetic field characterization apparatus as in claim 29, wherein said first temperature parameter is a lowest temperature data value and said second temperature parameter is a highest temperature value.

36. A method of manufacturing an electromagnetic field characterization apparatus as in claim 29, further comprising a mechanism adapted to move said electromagnetic source or the electromagnetic absorption material in relation to each other in order to manipulate either said electromagnetic field which is being measured or manipulate the electromagnetic absorption material to move it through the electromagnetic field which is being measured in order to produce a plurality of power density image maps each representing a different plane measurement of said electromagnetic field or a three-dimensional power density image map.

37. A method of manufacturing an electromagnetic field characterization apparatus as in claim 29, wherein said first processing sequence further selects additional said temperature sensor data frames in between said initial and final temperature sensor data frames and determines associated time differentials between consecutive said selected additional temperature sensor data frames, wherein said second processing sequence for calculating a power density data further serially calculates power density between each two of said selected temperature sensor data frames then said second processing sequence sums all of the power density data for each two consecutive temperature sensor data frame from said initial frame to said final frame to produce a final power density data.

38. A method of manufacturing an electromagnetic field characterization apparatus comprising:

providing an electromagnetic source adapted to emit electromagnetic field;

providing an electromagnetic absorption material adapted to receive said electromagnetic field;

providing a plurality of temperature sensors adapted to orient on said electromagnetic absorption material and output a plurality of temperature sensor data frames data, wherein said plurality of temperature sensors comprise a plurality of temperature sensor pixels and said plurality of temperature sensor data frame data each store a temperature data output from each said temperature sensor pixels;

providing a plurality of processing sequences comprising;

a first processing sequence adapted to select and store an initial and final temperature sensor data frame from said plurality of temperature sensor data frames based on a first and second temperature parameter, said first processing sequence further determines a differential temperature data associated with said initial and final temperature sensor data frames;

a second processing sequence for calculating a power density data associated with all or a portion of said plurality of temperature sensors and said final temperature sensor data frame, said second processing sequence determines said power density data based on a power density per said pixel calculation comprising a peak power density value based on a plurality of calculation elements comprising a coefficient of absorption of the electromagnetic absorption material, a coefficient of transmission of the electromagnetic absorption material, the final temperature of the electromagnetic absorption material, the initial temperature of the electromagnetic absorption material, emissivity of the electromagnetic absorption material, Stefan-Boltzmann constant, a specific heat of at least one heat sink, a volume of the at least one heat sink, a density of the at least one heat sink, a contact area between the electromagnetic absorption material and the at least one heat sink, a time differential between the initial and final temperature sensor data frames, and degrees of freedom of atoms or molecules that comprise the electromagnetic absorption material and a plurality of inputs to said power density per said pixel calculation including said differential temperature data, wherein said calculation is modified based on a particular said electromagnetic absorption material, wherein the modified calculation components are coefficient of absorption of the electromagnetic absorption material, a plurality of degrees of freedom data for atoms or molecules associated with said electromagnetic absorption material associated with a blackbody radiation calculation, emissivity of blackbody radiation associated with said electromagnetic absorption material, specific heat capacity of the at least one heat sink placed in proximity to said electromagnetic absorption material, density of the at least one heat sink, volume of the at least one heat sink, and area of interface between the at least one heat sink and said electromagnetic absorption material; and

a third processing sequence for producing at least one graphical user interface, said at least one graphical user interface comprises a power density image output produced based on a plurality of ranges of power density which depicts said power density data, said at least one graphical user interface also is adapted to display one or more said power density data associated with at least one of said plurality of temperature sensors.

39. A method of manufacturing an electromagnetic field characterization apparatus as in claim 38, further comprising providing a processing system adapted to process said plurality of processing sequences and produce a plurality of outputs comprising said power density image output.

40. A method of manufacturing an electromagnetic field characterization apparatus as in claim 38, further comprising providing a temperature control mechanism which provides cooling to said electromagnetic absorption material.

41. A method of manufacturing an electromagnetic field characterization apparatus as in claim 40, wherein said temperature control mechanism is a circulation fan.

42. A method of manufacturing an electromagnetic field characterization apparatus as in claim 38, wherein said electromagnetic source is a radio frequency source coupled to an electromagnetic field radiating structure.

43. A method of manufacturing an electromagnetic field characterization apparatus as in claim 38, wherein said plurality of temperature sensors comprises one or more infrared image sensing apparatus.

44. A method of manufacturing an electromagnetic field characterization apparatus as in claim 38, wherein said first temperature parameter is a lowest temperature data value and said second temperature parameter is a highest temperature value.

45. A method of manufacturing an electromagnetic field characterization apparatus as in claim 38, further comprising a mechanism adapted to move said electromagnetic source or the electromagnetic absorption material relation to each other in order to manipulate either said electromagnetic field which is being measured or manipulate the electromagnetic absorption material to move it through the electromagnetic field which is being measured.

46. A method for electromagnetic field characterization comprising:

providing an electromagnetic source adapted to produce an electromagnetic field;

providing an electromagnetic absorption material;

providing an array of temperature sensors;

providing a processing system and input/output system;

positioning said array of temperature sensors and said electromagnetic source to orient on said electromagnetic absorption material based on a desired measurement of said electromagnetic field produced by said electromagnetic source;

acquiring a plurality of temperature image data starting from a first point in time to final point in time attained after a peak temperature of said electromagnetic absorption material is reached by at least one temperature sensors in said array of temperature sensors or a predetermined point of time and saving temperature per pixel data and time associated with each temperature per pixel data to a Temperature Data per Pixel (TDPP) data array;

inputting data from said TDPP Array;

selecting an initial frame based on a comparison of all frames in said TDPP array and identifying one of said frames in said TDPP array having a coldest or lowest ambient temperature or based on determining a time prior to activation of said electromagnetic source;

selecting a final frame based on a comparison of all frames in said TDPP array and identifying one of said frames in said TDPP array having a highest temperature;

determining power density data associated with each said pixel in said initial and final frames based on a plurality of characteristics of said EM absorber including absorption coefficient, transmission coefficient, degrees of freedom, emissivity, Stefan-Boltzmann'"'"'s Constant associated with said electromagnetic absorption material, number of sides of said electromagnetic absorption material being cooled, specific heat capacity of a coolant used to cool said electromagnetic absorption material, density of said coolant, volume of said coolant, area that said coolant will be in contact with said electromagnetic absorption material, change in time between said initial and final frame capture, and an initial and final temperature data of the EM absorber.

47. A method as in claim 46, further comprising providing a temperature control mechanism which provides cooling to said electromagnetic absorption material.

48. A method as in claim 47 wherein said temperature control mechanism is a circulation fan.

49. A method as in claim 46, wherein said electromagnetic source is a radio frequency source coupled to an electromagnetic field radiating structure.

50. A method as in claim 46, wherein said array of temperature sensors comprises an infrared image sensing apparatus.

51. A method as in claim 46, wherein said plurality of temperature image data comprises a plurality of infrared image frame captures.

52. A method as in claim 46, wherein said first point in time is a time prior to activation of said electromagnetic source.