Method of simulating the absorption of plane waves using FEM software tools

Patent metadata

Field	Value
Publication number	US-9759693-B2
Application number	US-201213721088-A
Country	US
Kind code	B2
Filing date	Dec 20, 2012
Priority date	Dec 20, 2012
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

A novel and useful method of visualization by detection of EM radiation being irradiated or reflected from objects in the imager's field of view using Finite Element Method (FEM) simulation software tools. The methodology provides a verification method of antenna operation from an electrical point of view since bolometer performance cannot be estimated using regular antenna parameters such as directivity, gain, impedance matching, etc. as the bolometer does not behave as an antenna but rather behaves as an absorber. An incident wave is triggered on the absorber and the absorption of the bolometer structure is estimated using commercially available Finite Element Method (FEM) software (e.g., ANSYS® HFSS software, CST MICROWAVE STUDIO®, etc.). How much of the energy is reflected is subsequently measured. The energy which is not reflected is considered to be absorbed by the absorber.

First claim

What is claimed is:

1. A computer-implemented method of simulating absorption of plane waves using Finite Element Method (FEM) software tools, comprising:
defining a simulation in the Finite Element Method software tools of a structure having a single wave-port, wherein said structure comprises at least one of a pair of opposite faces having perfect magnetic conductor boundary conditions and a pair of opposite faces having perfect electrical conductor boundary conditions;
placing a simulation in the Finite Element Method software tools of a physical bolometer whose absorption is to be simulated within said structure, said bolometer having a physical structure comprising an antenna and a resistive load;
generating a simulation in the Finite Element Method software tools of an incident wave excitation by triggering a plane wave utilizing said wave-port;
determining power absorbed by said physical bolometer as a function only of total reflected energy based on results of the simulation in the Finite Element Method software tools; and
verifying operation of the physical bolometer based on the determined power.

2. The method according to claim 1 , wherein said structure comprises a rectangular simulation volume having a vacuum therein.

3. The method according to claim 1 , wherein said structure comprises first and second opposite faces having perfect magnetic conductor boundary conditions.

4. The method according to claim 1 , wherein said structure comprises third and fourth opposite faces having perfect electrical conductor boundary conditions.

5. The method according to claim 1 , wherein said structure comprises a bottom face perfect magnetic conductor.

6. The method according to claim 1 , wherein said structure comprises a bottom face perfect electrical conductor.

7. The method according to claim 1 , wherein said structure comprises a bottom face wave-port.

8. The method according to claim 1 , wherein said structure comprises a bottom face having a boundary condition in which the energy can be absorbed or escape while the energy can be calculated by the field calculator component of said software tool.

9. The method according to claim 1 , wherein the total absorbed power is one minus the total reflected energy.

10. The method according to claim 1 , wherein scattered electromagnetic fields are mathematically represented by one or more waveguide modes.

11. The method according to claim 1 , wherein power absorbed is calculated using the equation Absorption=1−Σ nm |S 00->nm | 2 where nm represents different possible transverse electric modes and S 00->nm represents scattering parameters between a transverse electromagnetic mode 00 and a transverse electric mode nm.

12. A computer-implemented method of simulating absorption of plane waves using Finite Element Method (FEM) software tools, comprising:
defining a rectangular simulation volume having six faces in the Finite Element Method software tools, wherein said rectangular simulation volume comprises at least one of a pair of opposite faces having perfect magnetic conductor boundary conditions and a pair of opposite faces having perfect electrical conductor boundary conditions;
placing a simulation in the Finite Element Method software tools of a physical bolometer whose absorption is to be simulated within said simulation volume, said bolometer having a physical structure comprising an antenna and a resistive load;
generating a simulation in the Finite Element Method software tools of an incident wave excitation by triggering a plane wave utilizing a wave-port on a top face of said simulation volume; and
determining power absorbed by said physical bolometer as a function only of total reflected energy based on results of the simulation in the Finite Element Method software tools; and
verifying operation of the physical bolometer based on the determined power.

13. The method according to claim 12 , wherein said simulation volume comprises first and second opposite faces having perfect magnetic conductor boundary conditions.

14. The method according to claim 12 , wherein said simulation volume comprises third and fourth opposite faces having perfect electrical conductor boundary conditions.

15. The method according to claim 12 , wherein said simulation volume comprises a sixth bottom face perfect magnetic conductor.

16. The method according to claim 12 , wherein said simulation volume comprises a sixth bottom face perfect electrical conductor.

17. The method according to claim 12 , wherein said simulation volume comprises a sixth bottom face wave-port.

18. The method according to claim 12 , wherein said simulation volume comprises a sixth bottom face having a boundary condition in which the energy can be absorbed or escape while the energy can be calculated by a field calculator component of said software tool.

19. The method according to claim 12 , wherein the total absorbed power is one minus the total reflected energy.

20. The method according to claim 12 , wherein scattered electromagnetic fields are mathematically represented by one or more waveguide modes.

21. The method according to claim 12 , wherein the power absorbed is calculated using the equation Absorption=1−Σ nm |S 00->nm | 2 where nm represents different possible transverse electric modes and S 00->nm represent scattering parameters between a transverse electromagnetic mode 00 and a transverse electric mode nm.

22. A computer-implemented method of simulating absorption of plane waves using Finite Element Method (FEM) software tools, comprising:
defining a rectangular simulation volume having first and second opposite faces having perfect magnetic conductor boundary conditions, third and fourth opposite faces having perfect electrical conductor boundary conditions, a fifth top face wave-port, and a sixth face boundary;
placing a simulation of a physical bolometer whose absorption is to be simulated within said simulation volume, said bolometer having a physical structure comprising an antenna and a resistive load;
generating a simulation of an incident wave excitation by triggering a plane wave utilizing said fifth face wave-port of said simulation volume; and
determining the power absorbed by said physical bolometer as one minus the total reflected energy based on results of the simulation.

23. The method according to claim 22 , wherein scattered electromagnetic fields are mathematically represented by one or more waveguide modes.

24. The method according to claim 22 , wherein the power absorbed is calculated using the equation Absorption=1−Σ nm |S 00->nm | 2 where nm represents different possible transverse electric modes and S 00->nm represent scattering parameters between a transverse electromagnetic mode 00 and a transverse electric mode nm.

Assignees

• IBM

Inventors

• Corcos Dan
• Elad Danny
• Kaminski Noam
• Klein Bernhard
• Kull Lukas
• Morf Thomas

Classifications

• G01J5/20

  using resistors, thermistors or semiconductors sensitive to radiation, e.g. photoconductive devices · CPC title

• G01J5/0837 Primary

  Microantennas, e.g. bow-tie · CPC title

• G01N30/00 Primary

  Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography {or field flow fractionation} (G01N3/00, G01N5/00, G01N7/00, G01N9/00, G01N11/00, G01N13/00, G01N15/00, G01N17/00, G01N19/00, G01N21/00, G01N22/00, G01N23/00, G01N24/00, G01N25/00, G01N27/00, G01N29/00 take precedence) · CPC title