SIMULATION OF WAVEGUIDE SIMULATION OF WAVEGUIDE SIMULATION OF WAVEGUIDE SIMULATION OF WAVEGUIDE SIMULATION OF WAVEGUIDE SIMULATION OF WAVEGUIDE SIMULATION OF WAVEGUIDE SIMULATION OF WAVEGUIDE
CIRCUITS AND ANTENNAS CIRCUITS AND ANTENNAS CIRCUITS AND ANTENNAS CIRCUITS AND ANTENNAS CIRCUITS AND ANTENNAS CIRCUITS AND ANTENNAS CIRCUITS AND ANTENNAS CIRCUITS AND ANTENNAS
WITH MMTWITH MMTWITH MMTWITH MMTWITH MMTWITH MMTWITH MMTWITH MMT--------BASED BASED BASED BASED BASED BASED BASED BASED
MODULAR SOFTWAREMODULAR SOFTWAREMODULAR SOFTWAREMODULAR SOFTWAREMODULAR SOFTWAREMODULAR SOFTWAREMODULAR SOFTWAREMODULAR SOFTWARE
Dept. Computational ElectromagneticsInstitute for Radio-Physics and Electronics NASU
Kharkov, Ukraine
A. Nosich
with inputs from A. Kirilenko and L. Rud
Examples of simulated waveguide circuits
Main ideas and parts1.1. Segmentation:Segmentation: decompose any decompose any
waveguide circuit into a sequence of waveguide circuit into a sequence of
regular segments of simple and multiregular segments of simple and multi--
connected waveguides,connected waveguides,
2.2. Modes: Modes: find vector modal base of each find vector modal base of each
segment,segment,
3.3. Matching: Matching: join segments via plane join segments via plane
junctions and calculate corresponding junctions and calculate corresponding
SS--matrices,matrices,
4.4. Assembling:Assembling: build the Sbuild the S--matrix of the matrix of the
whole circuitwhole circuit
Example of simulated filter configuration
SegmentationSegmentationSegmentation
Longitudinal segmentation
1.1. Reveal possible Reveal possible symmetriessymmetries,,
2.2. Determine Determine connectivityconnectivity of crossof cross--
sections,sections,
3.3. Introduce Introduce virtual segmentsvirtual segments of zero of zero
lengths,lengths,
4.4. Determine domains of Determine domains of overlappingoverlapping of of
the crossthe cross--sections of segments joint at sections of segments joint at
plane junctionsplane junctions
3D graphic editor based on AutoCADwire model. Example of editing
SegmentationSegmentationSegmentation
Search of modal bases
1.1. Split to Split to classesclasses of symmetry,of symmetry,
2.2. Introduce rectangular or circular subIntroduce rectangular or circular sub--
domains and domains and series expansionsseries expansions,,
3.3. Satisfy Satisfy matchingmatching conditions at subconditions at sub--
domain boundaries,domain boundaries,
4.4. Reduce the Reduce the eigenvalueeigenvalue problem to a problem to a
determinantdeterminant equationequation
5.5. If connectivity >1, findIf connectivity >1, find TEM modesTEM modes
from electrostatic problemfrom electrostatic problem
Modal basesModal basesModal bases
Electromagnetic solver interfaceAnalysis of the field patterns
Generalized S-matrices
For each junction:For each junction:
�� Input:Input: coordinates of overlapping coordinates of overlapping
domains,domains,
�� Method:Method: modemode--matching and matching and
coupling integrals,coupling integrals,
�� Output:Output: SS--matrix of a junction,matrix of a junction,
Final step: Final step:
automatic assembling of the full automatic assembling of the full
SS--matrix of the whole circuitmatrix of the whole circuit
3D graphic editor based on AutoCADSolid model
Plane junctionsPlane junctionsPlane junctions
Overall SOverall SOverall S---matrixmatrixmatrix
Electromagnetic solver interfaceAnalysis of the filter characteristics
EvanescentEvanescent--mode mode bandpassbandpass filtersfilters on singleon single-- and and doubledouble--ridged waveguidesridged waveguides
Improved stop Improved stop
band performanceband performance
Filters
Filters - interface
Specification windowFilter geometryFrequency responsesParasitic bandwidths analysis
EvanescentEvanescent--mode lowmode low--pass filter configurations and pass filter configurations and performance of an 11performance of an 11--pole doublepole double--ridge filterridge filter
Filters
Bandwidth
26-40 GHz
BandstopBandstop filters on the Efilters on the E--plane stubsplane stubs and and characteristics of a 5characteristics of a 5--pole filterpole filter
Filters
Mode converter
TETE1010→→TTEEn0n0 mode converter built on the Hmode converter built on the H--plane nonsymmetrical plane nonsymmetrical
truncated angled bend truncated angled bend ((input waveguideinput waveguide 2323хх10 10 mmmm))
Square waveguide
polarizer
NarrowNarrow--band polarizer built on a square waveguide with band polarizer built on a square waveguide with
squaresquare--corner cuts and its characteristicscorner cuts and its characteristics
Circular waveguide polarizer with rectangular ridges and Circular waveguide polarizer with rectangular ridges and
characteristics of the optimized 4characteristics of the optimized 4--element polarizerelement polarizer
Circular waveguide
polarizer
DualDual--mode mode bandpassbandpass filtersfilterswithwith tilted rectangular coupling irisestilted rectangular coupling irises
4
-
6
-
8
-
pole
Filters
Filters
4-1 8-2
Frequency responses of the designed 4Frequency responses of the designed 4-- and 8and 8--pole pole
dualdual--mode bandmode band--pass filterspass filters
Vacuum window in
circular waveguide
Vacuum windows with one and two dielectric plates in a Vacuum windows with one and two dielectric plates in a
circular waveguide and their characteristicscircular waveguide and their characteristics
7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5
1.00
1.02
1.04
1.06
1.08
1.10
VS
WR
Frequency, GHz
Waveguide28.5х12.6 мм
8.0 8.5 9.0 9.5 10.0 10.5 11.0 11.5 12.0
1.0
1.5
2.0
2.5
3.0
Theory
Measurement
Waveguide23.0х10.0 мм
VS
WR
Frequency, GHz
TE01
TE02
EE--plane bifurcation diplexersplane bifurcation diplexers
withwith oneone--step transitionstep transition
Diplexers
HH--plane bifurcation diplexersplane bifurcation diplexers
withwith oneone--step transitionstep transition
Diplexers
EE--tee based diplexerstee based diplexers
Diplexers
HH--tee based diplexerstee based diplexers
Diplexers
Diplexers
Frequency responses of the designed EFrequency responses of the designed E--tee based diplexer and tee based diplexer and
channel filters on symmetrical inductive iriseschannel filters on symmetrical inductive irises
Crossed slot coupler
CrossCross--slot coupler (Moreno coupler) and its characteristics for slot coupler (Moreno coupler) and its characteristics for
varying thickness of irises varying thickness of irises tt and angles of their rotation, and angles of their rotation, αα1,21,2
Multilayer lowpass filter
Multilayer lowMultilayer low--pass filter, waveguides whose mode bases have to pass filter, waveguides whose mode bases have to
be calculated during the filter analysis, and the filter responsbe calculated during the filter analysis, and the filter responses es
(black) compared with the moment method results (red)(black) compared with the moment method results (red)
1 2 3 4 5 6 7 8 9
60
50
40
30
20
10
0
|S11
|
|S21
||S11|, |S
21|, dB
Frequency, GHz
Dual-band septum
polarizer
DualDual--band septum polarizer and an example of its band septum polarizer and an example of its
characteristicscharacteristics
Dual-band orthomode
transducer
DualDual--band band orthomodeorthomode transducer and its characteristics transducer and its characteristics
within the Intelsat operation bandswithin the Intelsat operation bands
Dual-band corrugated
circular horn antenna
r
R
( )i
cb
( )i
ca
( )i
cg
( )i
ct
α
g t
( )n
ha( )n
hb
l
Fig. 1. Parameters of corrugated horn structure. Half of crossHalf of cross--section of a section of a
dualdual--band corrugated hornband corrugated horn
Antenna analysis:Antenna analysis:
•• Horn is considered as a Horn is considered as a
cascade of circular waveguide cascade of circular waveguide
junctionsjunctions
•• SS--matrices are determined matrices are determined
and assembled togetherand assembled together
•• Horn opens into a wide Horn opens into a wide
circular waveguide and circular waveguide and
radiation patterns are found by radiation patterns are found by
aperture integrationaperture integration
Dual-band corrugated
circular horn antenna
r
R
( )i
cb
( )i
ca
( )i
cg
( )i
ct
α
g t
( )n
ha( )n
hb
l
Fig. 1. Parameters of corrugated horn structure. Input dimensions: Input dimensions: rr=5 mm, =5 mm,
RR=27.5 mm, =27.5 mm, tt=0.4mm, =0.4mm,
NN1=4 slots in the throat and 1=4 slots in the throat and
NN2=25 slots in the flare 2=25 slots in the flare
sections, sections, αα=15deg=15deg
Antenna synthesis by numerical Antenna synthesis by numerical
gradients:gradients:
•• At first, return loss is minimized At first, return loss is minimized
over two operating bandsover two operating bands
•• Then, polarization purity and Then, polarization purity and
radiation pattern symmetry are radiation pattern symmetry are
tuned to prescribed valuestuned to prescribed values
•• Task example:Task example:TE11 mode incidence, horn bands: TE11 mode incidence, horn bands: 2020--21.5 GHz21.5 GHz & & 29.529.5--31.5 GHz31.5 GHz
inin--band return loss band return loss --25 dB, 25 dB,
peak peak XPolXPol --40 dB, pattern non40 dB, pattern non--uniformityuniformity
0.25 dB within 300.25 dB within 30--deg sectordeg sector
FarFar--field patterns and return loss vs. frequencyfield patterns and return loss vs. frequency
Dual-band corrugated
circular horn antenna
Conclusions
1.1. At IREAt IRE--KharkovKharkov, a modular full, a modular full--wave GMM software for the wave GMM software for the
waveguide circuits analysis, synthesis and optimization has waveguide circuits analysis, synthesis and optimization has
been developed since the 1980s.been developed since the 1980s.
2.2. This software can be adapted to the efficient and accurate This software can be adapted to the efficient and accurate
analysis and synthesis of certain types of antennas.analysis and synthesis of certain types of antennas.
3.3. The corrugated circular horn configurations that provide The corrugated circular horn configurations that provide
specified return loss, polarization purity, and radiation specified return loss, polarization purity, and radiation
pattern symmetry over 2 widely separated bands have pattern symmetry over 2 widely separated bands have
been demonstratedbeen demonstrated..
•• IEEE Trans. on MTT (IEEE Trans. on MTT (66))
•• Microwave and Optical Technology Letters (Microwave and Optical Technology Letters (44))
•• Int. J. RadioInt. J. Radio--Frequency and Microwave Computer Aided Frequency and Microwave Computer Aided
Engineering (Engineering (33))
•• J. Telecommunications Technology and ElectronicsJ. Telecommunications Technology and Electronics ((55))
•• Proc. European Microwave Conferences (Proc. European Microwave Conferences (1010))
•• IEEE MTTIEEE MTT--S Symposium Digests (S Symposium Digests (66))
•• Proc. Int. Polish Conferences on Microwaves and Radars (Proc. Int. Polish Conferences on Microwaves and Radars (77))
•• Proc. Int. Conferences Mathematical Methods in EM Theory (Proc. Int. Conferences Mathematical Methods in EM Theory (1515))
•• Proc. Int. Proc. Int. SympSymp. Physics and . Physics and EngnEngn. MM and Sub. MM and Sub--MM Waves (MM Waves (1616))
Relevant Publications on
Waveguide and Antenna Analysis,
Synthesis, and Design since 1994