Post on 10-May-2018
利用HFSS9.0的先进性进行微波无源器件的设计和优化
Passive Microwave Component Design and Optimization
Haiqiang Ding
Senior Application Engineer
Ansoft Beijing Office
Jolly Zhou
Senior Application Engineer
Ansoft Shanghai Office
AbstractChallenges of Modern Microwave Component and Antenna Design
Waveguide Slot Array Computer Aided Design and Simulation
Rapid Direction-Finding Antenna Array Design
Satellite Communication Antennas Simulation
Rotary Joint Optimization
Modern Microwave Component and Antenna Design
Higher Performance
More Complex
Complex Radiation Pattern
System Level Design
Design Cost and cycle
Benefits of using Electromagnetic Field Solvers
Make Good Thinking to Good Design
Decrease Instruments Time
Design Costs and Cycle
Human Resource
Requirements of Electromagnetic Field Simulators for Modern Design
Accuracy,Reliable and Fast
Simulation Capacity
Real Arbitrary 3D Structure
Easy to Use
Technical Support
Ansoft HFSS: Golden Tool for Antenna and Passive Microwave component Design
Powerful Features
Accuracy,Reliable and FastMore than 10,000 customer all over the word
Adaptive Meshing
Technical support
Waveguide Slot Array Computer Aided Design and Simulation
Waveguide Slot Array Antenna
Ground RadarRadar on Aircraft
Waveguide Slot Array Antennas are well used in Defense such as Radar on Fighter, Missile or ground.
•Good Antenna Gain, low side lobe and VSWR
•Good Mechanical performance
Waveguide Slot Array
Waveguide Slots
Slots in Waveguide Slot Array antennasEvery slot is different: depend on the array factor
Prototype for the slots is tiresomeUse HFSS design every slot and get design curve
Waveguide Slot
Broadwall Displaced Slot
Broadwall inclined Slot
Edge Wall Slot
Ansoft HFSS Broadwall Displaced Slot Design
Y martix in the test port will equal to the Ymartrix in the center of the slot when the distance is half of guide wave wavelengthTo get the guided wavelength, just perform a “ports only” solve in HFSSWhen the slot is resonant, Im(Y(11)) =0
Offset
Lg: Guided wave wavelength
length
¼ Lg ½ Lg
Short
Test Port
Ansoft HFSS Broad wall Displaced Slot Design
Build the simulation model in HFSS v9
Direct parametricVery easy to useSet variable in /HFSS/design
properties/local variables
Design parameterslength:resonant length of slot, to be optimizedOffset: Slot center displace from the waveguide center
Ansoft HFSS Broad wall Displaced Slot Design
When the slot is resonant, Im(Y)=0Use ABS(Im(Y)) as cost functionChange offset from 1mm to 8mm, step 1mm, optimize length (resonant length) at every pointDesign curve is generated
Ansoft HFSS Broadwall Displace Slot Design
Optimization variable setting in HFSS v9Length will be optimized
Ansoft HFSS Broad wall Displaced Slot DesignOptimization in HFSS v9Cost function changes when optimization
Broad wall Displaced Slot DesignGenerate Slot Design Curve
Design curve is generated by HFSS v9 and optimizationResonant length of wave guide slot vs. Offset distance
13.5
14
14.5
15
15.5
16
16.5
17
1 2 3 4 5 6 7 8
Offset(mm)
length(mm)
Ansoft HFSS Broad wall Inclined Slot Design
Y martix in the test port will equal to the Ymartrix in the center of the slot when the distance is half of guide wave wavelengthAlso, when the slot is resonant, Im(Y(11)) =0
Rang
Lg: Guided wave wavelength
length
¼ Lg ½ Lg
Short
Test Port
Ansoft HFSS Broad wall Inclined Slot Design
Inclined angle changes from 10 degree to 35 degree, 5 degree stepOptimize resonant length at every inclined angle
Broad wall Inclined Slot DesignGenerate Slot Design Curve
Resonant length of wave guide slot vs. Inclined Angle
14.95
14.955
14.96
14.965
14.97
14.975
14.98
10 15 20 25 30 35
Rang(deg)
length(mm)
Ansoft HFSS Waveguide Slot Array Antenna Simulation
The whole simulation model in HFSS v9, Frequency is 3cm bandAll coupling between the slots are taken into accountMore than 200 radiation slots and 40 coupling slotsVery large in electric sizeSymmetry can be used to reduce computation time
Ansoft HFSS Waveguide Slot Array Antenna Simulation
3D radiation pattern when two ports are in same phaseSimulation time(PC):
2:30 CPU time212,305 Tetrahedral
Ansoft HFSS Waveguide Slot Array Antenna Simulation
3D radiation pattern when two ports are 180 degree different in phaseZero lobe in Z axiesBeing a frequency domain solve, HFSS can get this without re-solve the project: just set the phase of the ports
Ansoft HFSS Waveguide Slot Array Antenna Simulation
Compare with test result (two ports in same phase)
Simulation Result:3dB lobe width: 3.7 degreeback lobe level: -34dBc
Test Result:3dB lobe width: 3.67 degreeback lobe level: -34dBc
Rapid Direction Finding Antenna Array Design
The Principle of Direction Finding
2#D
1#
3#
4#
r1 r0 r2
φ
In the traditional interferometer Direction-Finding
The Principle of Direction_FindingThe electric field of “incident wave” at the variousantennas is as follows:
)exp(sin4
ii
i jkrr
kkjIlE −×
=ωε
θπ
θ )4,3,2,1(=i
)exp()( 0 ii jkrrEE −=θ
The propagating path differences between various antennas by the “incident wave”:
D—length of the baseline, λ—wavelength ,θ—the elevation of “incident wave”,φ—the azimuth of “incident wave”
ϑϕλπφ coscos2
34D
=
ϑϕλπφ cossin2
12D
=
The Principle of Direction_Finding
The azimuth of “incident wave”
)(34
12
φφϕ arctg=
The accuracy of DF is very low when the incident wave comes from the specific direction (in parallel with the baselines)
The propagating path difference (PPD)VS the azimuthangle of “incident wave”
The PPD of pair at the invariant D
All terminals load 50Ω
0~3.3%
0~12.9%
The PPD of pair at the invariant DThe propagating path difference VS the azimuth angleof “incident wave”
Pair terminals load 50Ω
0~37.3%
0~6.9%;0~-28.7%
Muti-coordinates systems can be implemented by rotatingDF baseline (AiBi) system,
The Principle of High DF Accuracy
3A 4A
2A
nA
1 31A 1B
nB
2B
n 44B
1F3B
2
Design DF Array Completely in Software
Obtain the high DF antenna array system using muti-coordinates systems theory
Design parameters of the length of baseline, antenna and matching and compensating network using calibration projects
Simulate phase Distortion of theincident wave ina real DF system
Obtain the phase characteristic of any array with coupling between antennas by any incident wave in the real DF system .
The PPD of pair at the invariant DThe propagating path difference VS the azimuth angleof “incident wave”
pair terminals are opened
0~3.2%
0~2.5%
The PPD of pair at the invariant DThe propagating path difference VS the azimuth angleof “incident wave”
All terminals are opened0~9.7%
0~9.3%0~-2%
The propagating path difference VS the azimuth angleof “incident wave”
The PPD of pair at the variant D
pair terminals load 50Ω31~76.7%
5.5~8.3%-2.9~-27%
The propagating path difference VS the azimuth angleof “incident wave”
pair terminals load 50Ω
The PPD of pair at the variant D
0~-37.3%
0~3.4%0~-1%
The PPD of pair at the variant D
So, it is the effective way to improve the DF accuracyto enlarge the length of the baseline
We find that:When , The PPD are extended to 176.7%;When , The PPD are extended to 130 %
or, reduced to 70%;When , The PPD’s are almost equal to 0
λ17.05.0 == mD
λ1→D
λ5.0=D
The propagating path difference (PPD)VS the azimuthangle of “incident wave”
The PPD of pair at the Five Array
All terminals load 50Ω,D=3m
0~2.8%
-0.8~-5.5%0.9~6.5%
The propagating path difference (PPD)VS the azimuthangle of “incident wave”
The PPD of pair at the Five Array
All terminals load 50Ω,D=3m-0.8~-18%,0.4~15%
1.5~-6%1.8~42%。
The topological chart of antenna matching
The Matching and Compensating Network
n:1
L1 L2
R
1 n:1
L RC
2
n:1
LRC
3n:1
L R2
4R1
The Five Cells Array of DF
All terminals load matching and compensating Network ,D=3m
4:1
R1
R1
R2L Z0=50Ω
the azimuth angle of “incident wave”
antenna cell with matching network
The PPD VS the azimuth angle of “incident wave”
The Five Cells Array of DF
All terminals load matching and compensating network ,D=3m
2.3~2.8%
-1.9~2.9%
The PPD VS the azimuth angle of “incident wave”
The Five Cells Array of DF
All terminals load matching and compensating network ,D=3m
-2.2~9.2%
-2~30%
The Five Cells Array of DFThe error of the PPD VS the azimuth angle of “incident wave”
Satellite Communication Antennas Simulation
Satellite Communication Antennas Simulation(1)
Initial DesignScalar Horn Antenna
Satellite Communication Antennas Simulation(1)
Radiation pattern Simulation time:00:5:15 CPU time00:2:38 real time on dual CPU computer17,433 tetrahedral
Satellite Communication Antennas Simulation(1)
Add a dielectric len on the horn
Satellite Communication Antennas Simulation(1)
The radiation pattern on Phi=90degree is expandedSimulation time:00:9:05 Simulation time on Desktop PC30,028 Tetrahedral
Satellite Communication Antennas Simulation(2)
The initial designCircle Waveguide feededCone and the Circle plane reflector
Satellite Communication Antennas Simulation(2)
Initial Design resultThe radiation pattern does not meet design goalThe VSWR is OK, but the best t is not at the desired frequency
Desired working frequencyBest frequency
Satellite Communication Antennas Simulation(2)
At the best VSWR frequency, the radiation pattern seems closer to the desired
Satellite Communication Antennas Simulation(2)
Improved designWe get the desired radiation patternAll this can be done in one morning
Ansoft HFSS Rotary Joint Optimization
Initial Design in HFSS v8.5
Rotary Joint Simulation and Optimization
Ansoft HFSS Rotary Joint Optimization
Model in HFSS v9Direct parametricEasier to optimize
Ansoft HFSS Rotary Joint Optimization
VSWR=1.5
Optimized resultFrom 3.01GHz to 3.62GHz VSWR<l.5 Resonant in 3.84GHz
Ansoft HFSS Rotary Joint Optimization
Phase animation in HFSS v9 post processorFrom the Complex MagE plotting, we can get and calculate the maximum work power of this device: 103KW
ConclusionHFSS: the golden tool for Microwave Component Design
Accuracy, reliable and fastReal Arbitrary 3D Structure
You Build the Structure, Ansoft Solve the Maxwell’s EquationHappy Electromagnetics Design!