# US 8,543,357 B1 · RF power density and field characterization technique

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 8,543,357 B1
- Document ID: US8543357B1
- Status: Granted
- Kind: B1
- Application number: 12/983,230
- Filed: 2010-12-31
- Granted: 2013-09-24
- Earliest claimed: 2010-07-30
- Assignees: The United States of America as represented by the Secretary of the Navy
- Applicants: Peter Marandos; Grady Patterson; Kenneth Leeson
- Inventors: Peter Marandos; Grady Patterson; Kenneth Leeson
- Web page: https://patentgrep.com/patent/US8543357B1

## CPC

- G01J 5/0003: {for sensing the radiant heat transfer of samples, e.g. emittance meter}
- G01J 5/58: using absorption; using extinction effect
- H04N 23/20: for generating image signals from infrared radiation only
- G01J 5/485: {Temperature profile}
- G01J 2005/0077: {Imaging}
- Y10T 29/49002: Electrical device making
- G01J: MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY (light sources F21, H01J, H01K, H05B; investigating properties of materials by optical means G01N)
- H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## 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

### Claim 1

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;
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 power density formula defined in equation (2) as
1
1
-
τ
-
Γ
[
D
⁢
⁢
ɛσ
b
⁡
(
T
4
-
T
0
4
)
+
∑
All
⁢
⁢
Heat
⁢
⁢
Sinks
⁢
C
⁢
⁢
ρ
⁢
⁢
V
Δ
⁢
⁢
tA
⁢
(
T
-
T
0
)
]
and a plurality of inputs to said equation (2) including said differential temperature data, where Γ is a coefficient of absorption of the electromagnetic absorption material, τ is a coefficient of transmission of the electromagnetic absorption material, T is the final temperature of the electromagnetic absorption material, T0 is the initial temperature of the electromagnetic absorption material, ε is emissivity of the electromagnetic absorption material, σb is the Stefan-Boltzmann constant, C is a specific heat of at least one heat sink, V is a volume of the heat sink, ρ is a density of the heat sink, A is a contact area between the electromagnetic absorption material and the at least one heat sink, Δt is a time differential between the initial and final temperature sensor data frames, and D are degrees of freedom of atoms or molecules that comprise the electromagnetic absorption material, wherein said equation (2) is modified based on a particular said electromagnetic absorption material, wherein the modified equation (2) components are coefficient of absorption of the electromagnetic absorption material, said 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 said at least one heat sink placed in proximity to said electromagnetic absorption material, density of said at least one heat sink, volume of said at least one heat sink, and area of interface between said 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.

### Claim 2 (depends on 1)

An electromagnetic field characterization apparatus as in claim 1, 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.

### Claim 3 (depends on 1)

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

### Claim 4 (depends on 3)

An electromagnetic field characterization apparatus as in claim 3, wherein said temperature control mechanism is a circulation fan.

### Claim 5 (depends on 1)

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.

### Claim 6 (depends on 1)

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

### Claim 7 (depends on 1)

An electromagnetic field characterization apparatus as in claim 1, wherein said plurality of temperature sensors is a video camera adapted to record infrared or near infrared spectrum energy.

### Claim 8 (depends on 1)

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.

### Claim 9 (depends on 1)

An electromagnetic field characterization apparatus as in claim 1, 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.

### Claim 10 (depends on 1)

An electromagnetic field characterization apparatus as in claim 1, 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.

### Claim 11

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;
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 power density formula defined in equation (2) as
1
1
-
τ
-
Γ
[
D
⁢
⁢
ɛσ
b
⁡
(
T
4
-
T
0
4
)
+
∑
All
⁢
⁢
Heat
⁢
⁢
Sinks
⁢
C
⁢
⁢
ρ
⁢
⁢
V
Δ
⁢
⁢
tA
⁢
(
T
-
T
0
)
]
and a plurality of inputs to said equation (2) including said differential temperature data, where Γ is a coefficient of absorption of the electromagnetic absorption material, τ is a coefficient of transmission of the electromagnetic absorption material, T is the final temperature of the electromagnetic absorption material, T0 is the initial temperature of the electromagnetic absorption material, ε is emissivity of the electromagnetic absorption material, σb is the Stefan-Boltzmann constant, C is a specific heat of at least one heat sink, V is a volume of the heat sink, ρ is a density of the heat sink, A is a contact area between the electromagnetic absorption material and the at least one heat sink, Δt is a time differential between the initial and final temperature sensor data frames, and D are degrees of freedom of atoms or molecules that comprise the electromagnetic absorption material, wherein said equation (2) is modified based on a particular said electromagnetic absorption material, wherein the modified equation (2) 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 said at least one heat sink placed in proximity to said electromagnetic absorption material, density of said at least one heat sink, volume of said at least one heat sink, and area of interface between said 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.

### Claim 12 (depends on 11)

A method of manufacturing an electromagnetic field characterization apparatus as in claim 11, 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.

### Claim 13 (depends on 11)

A method of manufacturing an electromagnetic field characterization apparatus as in claim 11, further comprising providing a temperature control mechanism which provides cooling to said electromagnetic absorption material.

### Claim 14 (depends on 13)

A method of manufacturing an electromagnetic field characterization apparatus as in claim 13, wherein said temperature control mechanism is a circulation fan.

### Claim 15 (depends on 11)

A method of manufacturing an electromagnetic field characterization apparatus as in claim 11, wherein said electromagnetic source is a radio frequency source coupled to an electromagnetic field radiating structure.

### Claim 16 (depends on 11)

A method of manufacturing an electromagnetic field characterization apparatus as in claim 11, wherein said plurality of temperature sensors comprises one or more infrared image sensing apparatus.

### Claim 17 (depends on 11)

A method of manufacturing an electromagnetic field characterization apparatus as in claim 11, wherein said first temperature parameter is a lowest temperature data value and said second temperature parameter is a highest temperature value.

### Claim 18 (depends on 11)

A method of manufacturing an electromagnetic field characterization apparatus as in claim 11, 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.