Jun-jul-ago antes 197520.22 depois 197518.26 diferença-1.96.
FEKO내전자기해석솔버의...
Transcript of FEKO내전자기해석솔버의...
FEKO내전자기해석솔버의올바른선택법
2018.04.17.
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
2
발표내용
• FEKO 소개
• FEKO의시뮬레이션맵과주파수의연관성
• 다양한응용예에따른적정솔버의적용방법
• Antenna Design (안테나 설계)
• Antenna Placement (안테나위치선정)
• Electromagnetic Compability (EMC)
• Scattering / RCS
• 기타응용 (waveguides, microstrip circuits and bio-electromagnetics)
• 정리
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
3
Introducing FEKO
Electromagnetic
simulation
Altair FEKO is a leading comprehensive
electromagnetic (EM) analysis software
suite, widely used in many industries and
built on state of the art computational EM
(CEM) techniques, to provide users with
software that can solve a broad range of
electromagnetic problems.
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
4
FEKO Key Applications
Electromagnetic
Compatibility (EMC)
Multiphysics Analysis and Optimization
Antenna Design Others ScatteringAntenna Placement
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
5
FEKO UI Components – CADFEKO and Solver
• CADFEKO: Model creation / import, definition, simulation and output specification
• Solver: Performs calculations
CADFEKO
POSTFEKO
FEKO Solver
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
6
FEKO UI Components – POSTFEKO
POSTFEKO: Post processing of simulation results
CADFEKO
POSTFEKO
FEKO Solver
FEKO의시뮬레이션맵&
주파수의연관성
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
8
Solvers in FEKO – Simulation Map E
LE
CT
RIC
AL
SIZ
E
COMPLEXITY OF MATERIALS
FDTD
FEM
MLFMM
MoM
UTD
PO/RL-GO
Full-wave
Methods
(physically
rigorous solution)
Asymptotic
Methods
(high-frequency
approximation)
Hybridization to
solve large and
complex
problems
All solvers included in the
same package
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
9
Short Description of Methods
Method of Moments (MoM)Ideal for radiation and coupling analysis,
being applicable to problems involving
currents on metallic and dielectric structures.
Multi-level Fast Multipole Method
(MLFMM)MLFMM is an alternative formulation of the
technology behind the MoM and is
applicable to much larger structures than the
MoM, making full-wave current-based
solutions of electrically large structures a
possibility.
Finite Element Method (FEM)Ideal for problems with several dielectrics,
including inhomogeneous ones, which are
not efficiently solvable with the MoM.
Finite Difference Time Domain
(FDTD)Ideal for solving highly inhomogeneous
materials and wideband problems.
Physical Optics (PO)High frequency method based on currents,
ideal for electrically very large radiation and
scattering analysis.
Large element PO (LE-PO) is also available.
It uses an alternative set of basis functions
allowing mesh sizes of multiple wavelengths.
Ray Launching – Geometrical Optics
(RL-GO) Ideal for metal or dielectric electrically very
large scattering and radiation analysis. It is a
ray-based technique that models objects
based on optical propagation, reflection and
refraction theory. It is also known as the
Shooting and Bouncing Rays (SBR)
approach.
Uniform Theory of Diffraction (UTD)Ideal for electrically extremely large, PEC
structures, being the method based on rays
(not on currents, like PO).
… and
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
10
Hybridized Methods: Full-wave + Asymptotic Methods
• MoM hybridized with PO, LE-PO, RL-GO, UTD and FEM
• MLFMM hybridized with FEM, PO or LE-PO
Antenna:
MoM region
Coupling
Radiation Hazard Analysis of Cellular
Base Station Antenna using MoM/FEM
Human:
FEM region
MLFMM part
LE-PO region with
larger triangles
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
11
Solvers and Methods under Productivity Features
Features including other methods and
solvers focused on specific analysis,
including:
• Windscreen antenna modelling and
solution method.
• Complete integrated cable modelling tool
with Multiconductor Transmission Line
Method (MTL) launched in 2011.
• Model decomposition using equivalent.
sources of complex sources and receivers
• Large finite array solver.
• Characteristic Mode Analysis (CMA)
method.
Solver Introduction
MoM Since 1991
MoM/PO Since 1992
MoM/UTD Since 1994
MLFMM Since 2004
MoM/FEM Since 2005
MoM/RL-GO Since 2007
MLFMM/FEM Since 2010
MoM/LE-PO Since 2010
MLFMM/PO and
LE-PO
Since 2014
FDTD Since 2014
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
12
Memory Requirement Comparison of MoM and MLFMM
Number of
Unknowns
(N)
MoMMemory: N2
Run-time: N3
MLFMMMemory: Nlog(N)
Run-time: Nlog2(N)Examples
100 000 75 GB 1 GB
Military aircraft at 690 MHz
Ship (115 m x 14 m) at 107 MHz
Reflector antenna with aperture size 19λ
200 000 300 GB 2 GB
Military aircraft at 960 MHz
Ship (115 m x 14 m) at 150 MHz
Reflector antenna with aperture size 27λ
400 000 1.2 TB 4.5 GB
Military aircraft at 1.37 GHz
Ship (115 m x 14 m) at 214 MHz
Reflector antenna with aperture size 38λ
1 000 000 7.5 TB 12 GB
Military aircraft at 2.2 GHz
Ship (115 m x 14 m) at 340 MHz
Reflector antenna with aperture size 60λ
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
13
Electrical Size of an Aircraft
Frequency Electrical Size of Aircraft
Length Wing span
300 MHz 15 λ 9 λ
600 MHz 30 λ 17 λ
1.2 GHz 61 λ 34 λ
2 GHz 101 λ 57 λ
10 GHz 504 λ 284 λ
20 GHz 1009 λ 568 λ
300 MHz 600 MHz 1.2 GHz
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
14
Computation Resource Scaling for Aircraft Model
• Memory and runtime scaling for the SAAB JAS-39 Gripen:
• The results are normalized (300 MHz, MLFMM = 1) to highlight the factor increase in requirements as
a function of increasing frequency
• Furthermore, the graphs highlight the difference between requirements in the MLFMM and PO
methods.
• PO can solve the problem at 20 GHz where the plane is 1000λ long
Solution time scalingMemory scaling
2x Quad core Intel Xeon E5606 CPU, 2.13 GHz (8 processes total), 72 GB RAM Multi-threaded parallel processing was used on all 8 cores
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
15
Cross-Validation of Simulated Results
1.2 GHz 2.0 GHz
Leverage the different solvers to cross-validate the simulated results
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
16
Switching Between Solvers in CADFEKO
다양한응용예에따른적정솔버의적용방법
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
18
Antenna Design – Wire Antennas
MoM for wire antennas
(without dielectrics) MoM also for wire antennas
including dielectrics
(using FEKO’s MoM extensions to deal with
dielectrics, i.e. incl. Planar Green’s function
for infinite dielectrics, SEP for finite
dielectric using surface meshing, VEP for
finite dielectrics, dielectrically coated wires
and the windscreen antenna method)
Using VEP for electrically
small problems where high
permittivity or permeability are
modelled, like a ferrite core
with a wire around it
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
19
Antenna Design – Microstrip and Conformal Antennas
For microstrip antennas, consider:
• MoM with the Planar GF, SEP or VEP
• FEM, MoM/FEM
• FDTDMoM with SEP
MoM with Planar GF
MoM
For conformal antennas, consider:
• MoM
• FEM, MoM/FEM
• MLFMM
• MLFMM/FEM
MoM/FEM
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
20
Antenna Design – Arrays
For antenna arrays, consider:
• MoM, MoM/FEM
• MLFMM, MLFMM/FEM
• FEM
• FDTD
MoM
* Consider also DGFM, PBC and model decomposition
Method Memory Run-time
MoM 166 GB 13.2 hours
MLFMM 92 GB 4.6 hours
FEM 24 GB 0.1 hours
FDTD 2.7 GB 58.4 hours
FEM
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
21
Antenna Design – Windscreen and Wireless / Mobile Antennas
For windscreen antennas, consider:
• Windscreen antenna method with
MoM or MLFMM
For mobile and wireless antennas,
consider:
• MoM, MoM/FEM
• FEM
• FDTD
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
22
Antenna Design – Reflector and Dielectric Lens Antennas
For reflector antennas, consider:
• MLFMM or MLFMM with point source
• PO or LE-PO or RL-GO with point
source
MLFMM
Point
source
RL-GO
For dielectric lens antennas, consider:
• MoM (with SEP or VEP)
• MLFMM
• RL-GO
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
23
Antenna Placement Using MoM
Standard mesh /10
20.434 triangles
30.426 unknowns
Coarse mesh 1.2
987 triangles
15.813 unknowns
Typically use MoM for problems with electrical
sizes of up to 10-15 (and depending on the
available resources)
Rod antenna on MCC Car at 100 MHz
Considering also MoM with High Order Basis Functions (HOBF)
RCS illuminated with a plane wave at 900 MHz
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
24
Antenna Placement using MLFMM
MLFMM MoM
9.80 GBytes 896 GBytes
Antenna array mounted on
Iridium Satellite
Typical uses consider MLFMM for sizes from around 10 of up to 100 (or more
depeding on the available resources)
VHF 126 MHz Antenna
on Bottom Position
Antenna at 1 GHz
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
25
Antenna Placement with Hybrid and Asymptotic Methods
193.212 triangles hybrid MoM/PO
For problems with sizes from 20-30 to 1,000 consider:
• Hybrid methods based on MoM with PO or LE-PO or RL-GO
• Hybrid methods using MLFMM with PO or LE-PO or FEM
MLFMM
LE-PO
SATCOM antenna on aircraft using MLFMM/LE-PO
MLFMM
FEM
2.4 GHz planar array on missile
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
26
Antenna Placement using UTD
For problems with electrical sizes > 500 consider UTD
Example of 10 GHz radar antenna at 10 GHz on 102m long frigate
(and using model decomposition)
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
27
EMC – HIRF, Lightning Analysis or EMP
The aircraft geometry on the first row above is part of the CEMEMC workshop and corresponds to a morphed version of EV55, Intellectual Property of EVEKTOR,
spol. s r.o. and the HIRF SE Consortium (HIRF-SE FP7 EU project)
Magnetic field strength at 50 MHz
Magnetic field strength at 1 GHz
Exit point
Strike point
Antenna 1
Antenna 2Double exponential pulse
Typically consider MoM, MLFMM or FDTD
HIRF Application
Lightning stike on airborne platform (and using time analysis in POSTFEKO)
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
28
Method RAM (GB)
Simulation
time
(hours) Hardware
MoM
(SEP)17.84 1.36
parallel 8x
cluster
FDTD 1.96 0.18
1x GPU,
NVIDIA
Tesla K20c
EMC – Electromagnetic Pulses (EMP) with FDTD
For EMP problems dealing with complex structures and multiple dielectrics
consider FDTD
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
29
EMC – Cable Modelling in FEKO
FEKO also includes a Multiconductor Transmission Line (MTL) method to solve
cable problems, used with FEKO’s field solvers to compute the external fields and
currents that couple to/from such complex cables bundles
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
30
EMC – Cable analysis with MTL and MoM or MLFMM
HIRF impact on systems in a UAV
Coupling analysis between cable
(connecting control electronics in engine
to tail light) and 3G antenna Coupling analysis of radiated PCB emissions
into cable harness and windscreen antenna
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
31
EMC – Shielding Analysis
Example of magnetic
shielding from a steel
sphere from as low
as 60 dB
FEKO
Other CodeFEKO
FEKO
Use MoM with SEP or VEP, including
the high shielding formulation
Consider FDTD for shielding analysis
of complex and detailed structures
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
32
EMC – Radiated Emissions and Immunity
For the simulation of radiated emissions or immunity tests typically consider
MoM or MLFMM
DUT
EMC antenna
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
33
EMC – Radiation Hazard Analysis
For RADHAZ, when no human body models are included, consider MoM and
MLFMM (and hybrid or asymptotic methods if required)
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
34
Radar Cross Section (RCS)
1 10 100 1000
MoM
MLFMM
LE-PO
RL-GO
RCS at 75 MHz (ship length 30)
Model size in
Consider the following methods:
RCS at 10 GHz (ship length 4000)
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
35
Others – Microstrip circuits
Interdigital filter on a
lossy dielectric substrate
with a metallic enclosure
Design and currents on a triple split
ring resonator at 2 GHz
Shunt microstrip spiral
Slotted planar structure
Consider MoM, MoM/FEM, FEM and FDTD
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
36
Others – Waveguide Components and Devices
MoM (SEP) MoM / FEM FEM
Metallic Triangles 4996 7490 6639
Dielectric Triangles 922 2442
Tetrahedral Elements 21228 48106
Modal Port Triangles 326
Runtime per
frequency point **
272 sec 1123 sec 83 sec
Memory per process 277 MByte 784 MByte 190 MByte
Model
** Xeon® E5606 2.13GHz: 4 processes (cores) on 1 CPU
Example of a two-path cut-off dielectric resonator filter to show the solvers to
mainly consider:
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
37
Others – Radomes
Dielectric-layered wall radomes
and FSS radomes
To characterize the radome material use MoM
with the Planar Green’s Functions and PBC
For the radome with antenna:
• MoM or MoM/FEM for small electrical sizes
• For electrical sizes > 7-10 use
• MLFMM
• MLFMM/FEM
• RL-GO with point source
• If the wall of the radome if electrically thin
use MoM, MLFMM or RL-GO with TDS (Thin
Dielecric Sheet)
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
38
Others – Bioelectromagnetics
Antenna:
MoM region
Coupling
Human: FEM
regionMaximum
localised
SAR
High e-field
values
Low
e-field
values
Consider MoM/FEM, MLFMM/FEM or FDTD and when including human body
models
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
39
Others – Bioelectromagnetics in MRI
empty coil
MoM
coil & homogenous
phantom
MoM
coil & anatomical
head phantom*
MoM+FEM
coil & anatomical head
phantom**
FDTD
triangles 514 4038 514 - -
tetrahedral - - 132 572 - -
voxels - - - 2.76 M(4mm phantom) 19.1 M(1.75mm phantom)
runtime < 1 min 12 min 48 min 26 min 5.6 hrs
RAM 4 MB 0.97 GB 3.3 GB 570 MB 2.9 GB
* simulated on a clusters with parallel 8x, ** simulated with GPU acceleration
32 tuning
caps
RF shield
2 voltage
sources for
quadrature
IQ feeding
16 rungs
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
40
Others – Bioelectromagnetics – Human Body Models
Articulated
(parametric)
Human (SEP)
Standing Human
(FEM)
Articulated Hand
(SEP) IEEE Head (SEP)
Visible Human
Full Model
(Inhomogeneous
FEM)
Visible Human
Head and
Shoulders
(Inhomogeneous
FEM)
Visible Human
Head
(Inhomogeneous
FEM)
IEEE SAM
(Homogeneous
FEM)
Hugo (4 Organs
FEM)
Using geometry
cards in
EDITFEKO.
Parametric i.e.
change positions,
sit, stand, raise
arms, bend legs
etc. The mesh
size will change
with frequency and
has been tested
up to 900 MHz.
Model is based on
the Articulated
Human. The
model consists of
334,733
tetrahedrals (8mm
size) and can be
used for runs up to
1GHz. Requires
more than 2
GByte of RAM.
Using geometry
cards in
EDITFEKO.
Change position of
fingers, 16
degrees of
freedom. (Tested
up to 1800 MHz)
This CADFEKO
model is a triangle
mesh of the inner
layer of the IEEE
SAM phantom.
The minimum
triangle length is
10mm. The model
is set up for 1800
MHz. +- 2 GByte
of RAM required.
The model
contains 2.2 mil
tetrahedrals (8mm
size) and is
suitable up to
1GHz. Requires a
64bit machine and
will use +- 10
GByte of RAM.
The model
contains 300,000
tetrahedrals (8mm
size) and can be
used up to 1 GHz.
Can be solved on
a 32bit machine
with 2 GByte of
RAM.
The model
contains 900,000
tetrahedrals (4mm
size) and can be
used up to 2GHz.
Requires a 64bit
machine and will
use more than 2
GByte of RAM.
5mm tetrahedral
mesh of the older
IEEE SAM
phantom and a
20mm tetrahedral
mesh air box
around the head.
The model is set
up for 1800 MHz.
Requires +- 1.4
GByte of RAM
(with hertzian
dipole as antenna
(MoM)).
The model has 5
different media:
brain, lungs, eyes,
muscle and an
outer air shell. The
model contains
749,507
tetrahedrals (8mm
size) and can be
used up to 1GHz.
Requires more
than 2 GByte of
RAM.
All of the above phantoms can also be used with the FDTD solver in FEKO
Copyright © 2018 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
41
Summary Table and Remarks
Remember to check out
www.altairhyperworks.com/feko
Get in touch with Altair Korea
감사합니다.