unclassified
Missiles & NCW Division
R & D and Engineering
Directorate
ADVANCED DEFENCE
SYSTEMS Ltd.
Design and Optimization of an Antenna
using CST Microwave Studio and
modeFRONTIER
ESTECO UM2010 , Trieste 27-28 May 2010
Y. Kaldor - Rafael, S. Poles, F. Bernasconi – EnginSoft , E. Leroux – CST
1
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unclassified
Missiles & NCW Division
R & D and Engineering
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ADVANCED DEFENCE
SYSTEMS Ltd.
Overview
The following slides describe the design
process of a small antenna located on a large
platform.
The platform dimensions are : 13λ x 3λ x 3λ
( λ is the wavelength of the antenna)
2
RAF#3030180
UNC/8/30783/10
Proprietary of Rafael - Armament Development Authority Ltd
20 May 2010
unclassified
Missiles & NCW Division
R & D and Engineering
Directorate
ADVANCED DEFENCE
SYSTEMS Ltd.
Requirements
The Antenna is required to perform over a 30%
Frequency Bandwidth.
Matching Specification – over the full Bandwidth:
Return Loss : -8 dB max
VSWR 2.2:1 max
Difficulties
Tight Space – therefore required small antenna
dimensions
The environmental conditions under which the
antenna is required to perform are harsh.
3
RAF#3030180
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20 May 2010
unclassified
Missiles & NCW Division
R & D and Engineering
Directorate
ADVANCED DEFENCE
SYSTEMS Ltd.
The Solution
The antenna chosen as a solution is a
combination of a Slot Antenna and Travelling
Wave Antenna.
The Antenna was modeled and simulated
using CST Microwave Studio for return loss
and radiation pattern performance.
4
RAF#3030180
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20 May 2010
Missiles & NCW Division
unclassified
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SYSTEMS Ltd.
Initial Simulation Results
Matching over the full
frequency range was nearly
impossible due to dimension
constraints and coupling
from the platform
R & D and Engineering
Directorate
Specification
Optimization design Goal
Simulated Return loss was
initially very poor.
Sufficient performance was
obtained over 6% bandwidth
only.
5
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Missiles & NCW Division
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R & D and Engineering
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SYSTEMS Ltd.
The parameterized CST model
Initially the parameters
which mostly effect the
matching performance
were identified.
r
p
h
The CST model was
regenerated using these
parameters.
H
L
Input port
6
RAF#3030180
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20 May 2010
unclassified
Missiles & NCW Division
R & D and Engineering
Directorate
ADVANCED DEFENCE
SYSTEMS Ltd.
modeFRONTIER - Optimization Workflow
Input Variables
slot_length
stub
r_stub
pin_dist
partstub
Output Variables
Design Objective
slot_h
Design Constraint
R_loss_f_low
R_loss_f_cen
Minimize(maximum)
Maximum < -10 dB
R_loss_f_high
7
RAF#3030180
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20 May 2010
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unclassified
R & D and Engineering
Directorate
ADVANCED DEFENCE
SYSTEMS Ltd.
mF - Design Space
Post Processing
Bubble Chart
8
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unclassified
R & D and Engineering
Directorate
ADVANCED DEFENCE
SYSTEMS Ltd.
mF - Design Space
Post Processing
Parallel Coordinate
Chart
9
RAF#3030180
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20 May 2010
unclassified
Missiles & NCW Division
R & D and Engineering
Directorate
ADVANCED DEFENCE
SYSTEMS Ltd.
modeFRONTIER - Design Space
post processing charts
The various post processing charts help us
understand the physics of the problem.
In this sense the design space charts are
valuable decision making tools.
The various charts depict the full design space,
the history of the optimization an its progress
towards the optimal solution
Optimization using modeFRONTIER allows
Robust Design
10
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20 May 2010
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Before Optimization
R & D and Engineering
Directorate
Return Loss and VSWR Performance
Specification
Optimization Goal
Flow
Fcenter
Fhigh
ohm50
11
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20 May 2010
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Missiles & NCW Division
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SYSTEMS Ltd.
After Optimization
R & D and Engineering
Directorate
Return Loss and VSWR Performance
Specification
Optimization Goal
Flow
Fcenter
Fhigh
ohm50
12
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Missiles & NCW Division
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Directorate
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SYSTEMS Ltd.
Summary and Results
Return loss and VSWR performance were
highly improved using the optimization
process.
34% bandwidth was obtained!!
The optimization process was automatic
Few hundred runs were made, several
times.
13
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Missiles & NCW Division
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Summary and Results cont...
The antenna was manufactured and
measured.
Results are presented on the next slide
14
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Comparison of Measured vs. Simulated
Return Loss Performance
Specification
Simulated
Measured
Flow
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Fcenter
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Fhigh
20 May 2010
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Missiles & NCW Division
R & D and Engineering
Directorate
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SYSTEMS Ltd.
The Next Step…..
The next step is making a multidisciplinary
optimization using modeFRONTIER
The optimization model will include:
– ProE node
– Ansys node
– CST node
16
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The Model…..
R & D and Engineering
Directorate
UNC/8/30783/10
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20 May 2010
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Missiles & NCW Division
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Directorate
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SYSTEMS Ltd.
Thank You
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