1 the university of mississippi department of electrical engineering center of applied...
TRANSCRIPT
1
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Atef Z. Elsherbeni [email protected]
The University of Mississippi
Electromagnetic Scattering From Chiral Media
Mohamed H. Al Sharkawy [email protected]
The University of Mississippi
Veysel [email protected]
Syracuse University
Ercument [email protected] University
Samir [email protected]
wKuwait University
2
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Outline Objectives Properties of Chiral material Example of Chiral Objects Problem Geometry Solution Techniques
FDTD Solution
Boundary Value Solution
Iterative Solution Verifications Numerical Results and Applications
Conclusion
3
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Objectives
Techniques for the scattering from arbitrary shaped two-dimensional chiral, dielectric and conducting scatterers.
RCS reduction and field focusing using composite scatterers.
4
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Properties of Chiral Material Unlike dielectric or conducting cylinders,
chiral scatterers produce both co-polarized and cross-polarized scattered fields.
A chiral medium is therefore characterized by right-hand circularly polarized waves (RCP) and left-hand circularly polarized waves (LCP).
Coating with chiral material can reduce or enhance the radar cross-section of targets.
A short metallic helix as a chiral object and its enantiomorphism.
5
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
A sample of chiral material manufactured by a Finnish company. The sample measures 15 cm in diameters.
A closer view of the individual helices and their orientation.
Example of Chiral Objects
6
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Chiral Media Parameters
2/ 1c i i i
xxkk 21
k
c
or c is the chiral admittance
k is the wave number, depending on the chirality material
is the chirality parameter
7
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Constitutive Relation for the Chiral Material
,c cD E j B B H j E ejt is assumed
Waves in a chiral medium can be expressed as a superposition of RCP (R) and LCP (L) waves
1, cE R L H j R L
Maxwell’s equations in chiral medium:
2
c
c c
E j H E M
H j E H J
8
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Time Domain Solution Technique
9
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Multiple Frequency FDTD Formulation for Chiral Media
Using Maxwell’s equations and applying the 2nd order central difference approximation for the ejt time harmonic variation , we get
0 01, 2
0 0
0 01, 2
0 0
( , , )
( , , )
n xscat x x x
x x x
n xscat x x x
x x x
jtE i j k M N
jtH i j k M N
Where Mx and Nx are defined in terms of field components at previous time.
10
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Multiple Frequency FDTD Formulation for Chiral Media
0 0 0.5 0.5, , , ,
0.5 0.5 1, , , ,
0 0
1( , , ) ( , , ) ( , , 1) ( , , )
( )1( , 1, ) ( , , ) ( , , ) ( , , )
n n n nxx scat x scat x scat y scat y
n n n no xscat z scat z inc x inc x
i
jM H i j k E i j k E i j k E i j k
t t z
E i j k E i j k H i j k H i j ky t
jE
t
1 0.5 0.5, , , ,( , , ) ( , , ) ( , , ) ( , , )n n m n n
nc x inc x x inc x scat xi j k E i j k H i j k H i j k
0 0 0.5 0.5, , , ,
0.5 0.5 1, , , ,
0 0
1( , , ) ( , , ) ( , , ) ( , , 1)
( )1( , , ) ( , 1, ) ( , , ) ( , , )
n n n nxx scat x scat x scat y scat y
n n n noscat z scat z inc x inc x
i
jN E i j k H i j k H i j k H i j k
t t z
H i j k H i j k E i j k E i j ky t
jH
t
1 0.5 0.5, , , ,( , , ) ( , , ) ( , , ) ( , , )n n e n n
nc x inc x inc x scat xi j k H i j k E i j k E i j k
11
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Reflection and Transmission from a One Dimensional Chiral Slab of r = 2 and = 0.3
0 0, 0 0,
incEtranE
refE
x
z
0.1m
, ,r r
Co-Polarized Field.
Cr-Polarized Field.
12
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Scattering from a Chiral Sphere using the FDTD at 1 GHz with r = 4
7.2r cm
0 0, incE
x
z
, ,r r
13
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Scattering from a Chiral Sphere using the FDTD at four different frequencies of r = 4 and = 0.5
7.2r cm
0 0, incE
x
z
, ,r r
14
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Scattering from a Chiral Sphere using the FDTD at four different frequencies of r = 4 & = 0.5
7.2r cm
0 0, incE
x
z
, ,r r
15
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Frequency Domain Solution Techniques
16
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Problem Geometry Conducting Cylinder
Dielectric Cylinder
Chiral CylinderyM
xMM
1x
y
0
'
i'
j
'
j
yj
xjyi
xi
y1
x1
dij
'
i
ji
17
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Plane Wave Excitation-Incident E & H
E-polarized incident wave TMz
The corresponding component of the H-polarized incident wave
'0 0 0 0
'00 0
'cos( ) cos( )0
'cos( )0 0
( , )
( )
i i i i
ii i
jk jkincz i i
jnjk nn i
n
E E e e
E e j J k e
''00 0cos( ) '0
00
( , ) ( ) ii i jnjkinc ni i i n i
n
EH e j J k e
j
0
18
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Scattered and Internal Co-Polarized Fields
Cin , Ain and Bin are unknown coefficients.
0
'
(2)0 0
0
(2)00
0
' '0
( , ) ( )
( , ) [ ( ) ( )]
( , ) ( )
( , ) ( ) ( )
i
i
i
i
jnszi i i in n i
n
jnczi i i in n i in n i
n
jnsi i i in n i
n
jnci i i in n i in n i
nci
E E C H k e
E E A J k B J k e
EH C H k e
j
EH A J k B J k e
j
19
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Scattered and Internal Cross-Polarized Fields
Din , Ain and Bin are unknown coefficients.
0
(2)00
0
0
(2) '0 0
' '0
( , ) ( )
( , ) [ ( ) ( )]
( , ) ( )
( , ) ( ) ( )
i
i
i
i
jnszi i i in n i
n
jnczi i i in n i in n i
nci
jnsi i i in n i
n
jnci i i in n i in n i
n
EH j D H k e
EH j A J k B J k e
E E D H k e
E E A J k B J k e
20
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Boundary Value Solution(BVS)
21
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Boundary Conditions at the Surface of One Chiral Cylinder (Cylinder “i”, i = ai )
To solve for the unknown coefficients, the boundary conditions must be applied on cylinder i
czi
M
g
szg
inczi EEE
1
ci
M
g
sg
inci HHH
1
czi
M
g
szg HH
1
ci
M
g
sg EE
1
These four equations are repeated for all M cylinders.
22
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
(2)0 0
[ ( ) ](2)0 0 0
( , ) ( )
( , ) ( ) ( )
g
i ig
jnszg g g gn n g
n
j m m nszg i i gn m i m n ig
n m
E E C H k e
E E C J k H k d e
Transformation of Scattered Fields
The scattered field components from the gth cylinder in terms of the local coordinates of the ith cylinder
x
y
0
'
i'g
'g
yg
xgyi
xi
dig
'
i
gi
23
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Transformation of Scattered Fields
The scattered field components from the gth cylinder in terms of the local coordinates of the ith cylinder
0(2)
0 0
0 [ ( ) ]
' (2)0 00
[ ( ) ]0
(2)0 00
[ ( ) ]0
( ) ( )( , )
( ) ( )( , )
( ) ( )( , )
i ig
i ig
i ig
m i m n igszg i i gn j m m n
n m
m i m n igsg i i gn j m m n
n m
m i m n igszg i i gn j m m n
m
J k H k dE E C
e
J k H k dEH C
j e
J k H k dEH j D
e
' (2)0 0
0 [ ( ) ]
( ) ( )( , )
i ig
n
m i m n igsg i i gn j m m n
n m
J k H k dE E D
e
24
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Determining the External Coefficients Cgn and Dgn
M
g n
niggn
niggn
i RDSCV1
M
g n
niggn
niggn
i RDSCV1
)cos(0'
0'
0''
0
)(
)(
)(
)(
iijk
i
i
i
ii
i eakJ
akJ
akJ
akJvV
From the application of the boundary conditions on all M cylinders
Where
25
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
nigS
nigR
0 0 ngi ,
'
'
J
hv
J
hi
'
'
J
hv
J
hi
'
'
J
h
J
hvi
J
hv
J
hi'
'ngi ,
'
J
Hv
J
H ni
n
'
J
Hv
J
H ni
n
'
J
H
J
Hv nn
i
J
Hv
J
H ni
n'
gi
Solving for the External Coefficients Cgn and Dgn
26
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Solving for the Internal Coefficients Agn and Bgn
'
'
'
'
'
'
'
'
lli
llili
lli
llili
lli
lil
lli
ilil
JJv
hhCv
JJv
hhDv
JJv
JvJ
JJv
JvJA
'
'
'
'
'
'
'
'
lil
llili
lli
llili
lli
lli
lil
lilil
JvJ
hhDv
JJv
hhCv
JJv
JJv
JvJ
JvJB
27
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Used Variables:
)(
)(
0
0)2(
i
i
akJ
akHh
)(
)(
0'
0)'2(
'
i
i
akJ
akHh
)(
)(
0 i
i
akJ
akJJ
)(
)(
0'
''
i
i
akJ
akJJ
)(
)(
0 i
i
akJ
akJJ
)(
)(
0'
''
i
i
akJ
akJJ
)cos( 0''
0 iijki eVignj
ignn edkHH)(
0)2( )(
20 1
rrci
iv
28
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Iterative Solution(IS)
29
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Algorithm for Iterative Solution
• Stage 1: Apply the boundary condition on the surface of each cylinder, as the incident field is due to an external source.
• Stage 2: The incident field on each cylinder is produced by the scattered field from all other cylinders.
inc s czi zi ziE E E
inc s ci i iH H H
s czi ziH H
s ci iE E
1
Ms s czg zi zi
gg i
E E E
1
Ms s cg i i
gg i
H H H
1
Ms s cg i i
gg i
E E E
1
Ms s czg zi zi
gg i
H H H
0 0 0 0, ,C D A and B
1 0 1 0
1 0 1 0
( ), ( )
( ) ( )
C C D D
A A and B B
30
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Algorithm for Iterative Solution
' '0 0
(2) (2) '0 0I
' '0 0
(2) ' (2)0 0
( ) ( ) ( ) ( )
'( ) ( ) ( ) ( )C
( ) ( ) ( ) ( )
( ) ( ) '( ) ( )
i i i i i
i i i i i
i i i i i
i i i i i
J k a J k a v J k a J k a
H k a J k a v H k a J k a
J k a J k a v J k a J k a
v H k a J k a H k a J k a
' '0 0
(2) (2) '0 0I
' '0 0
(2) ' (2)0 0
( ) ( ) ( ) ( )
'( ) ( ) ( ) ( )D
( ) ( ) ( ) ( )
( ) ( ) '( ) ( )
i i i i i
i i i i i
i i i i i
i i i i i
v J k a J k a J k a J k a
H k a J k a v H k a J k a
J k a J k a v J k a J k a
v H k a J k a H k a J k a
(2) (2) '0 0
(2) (2) '0 0I
(2) (2) '0 0
(2) ' (2)0 0
'( ) ( ) ( ) ( )
'( ) ( ) ( ) ( )X
'( ) ( ) ( ) ( )
( ) ( ) '( ) ( )
i i i i i
i i i i i
i i i i i
i i i i i
v H k a J k a H k a J k a
H k a J k a v H k a J k a
v H k a J k a H k a J k a
v H k a J k a H k a J k a
( ) ( )I 0 (2) I 0 (2)0 0
1 11
I
C ( ) D ( )
X
ig ig
M Mj n j n
gn n ig gn n igg n g ng i g i
i
C H k d e D H k d e
C
31
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Matrix Formulation
1 1p p pC TC C RC D
1 1p p pD TD C RD D
1
p
p pi
pM
C
C C
C
1, 1,
2,1 2,1 2,
,
,1 ,
0
0
0
j M
M
i j
M M j
T T
T T T
T T
T T
1,1 1,, ,
,,
,
,1 ,, ,
ni j i j
ni j
i j
m m ni j i j
T T
TT
T T
(1, )
(1, )
(1,2 1)
(1,2 1)i
j
i M
j M
m N
n N
where
32
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Bistatic Scattering Cross Section of Five Perfectly Conducting Cylinders
Each cylinder has radius = 0.1 and their centers are separated by 0.5 due to a TM plane wave incident at 0=180
y
x
* Atef Z. Elsherbeni, “A comparative study of two-dimensional multiple scattering techniques,” Radio Science, vol. 29, pp. 1023-1033, July-August 1994.
50 100 150 200 250 300 350-10
-5
0
5
10
15
(degrees)
/ 0
(d
B)
BVSBVSITS
33
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Echo-Width of a Homogenous Chiral Strip
2, 3, 0.0005,
frequency =300 MHzr r c
(degrees)
Ech
o W
idth
(dB
/m)
* Michael S. Kluskens and Edward H. Newman, “Scattering by a Chiral Cylinder of Arbitrary Cross Section,” IEEE Trans. Antennas Propagate., vol. 38, pp. 1448-1455, Sept. 1990.
34
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Echo-Width of an Inhomogeneous Chiral Strip
2, 3, 0.0005,
frequency =300 MHzr r c
(degrees)
Ech
o W
idth
(dB
/m)
* Michael S. Kluskens and Edward H. Newman, “Scattering by a Chiral Cylinder of Arbitrary Cross Section,” IEEE Trans. Antennas Propagate., vol. 38, pp. 1448-1455, Sept. 1990.
0.0005c 0.0005c
35
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
= 0.041
Co-Polarized
X-Polarized
Dielectric 0.2
0.4
0.6
0.8
1
30
210
60
240
90
270
120
300
150
330
180 0
0.2
0.4
0.6
0.8
1
30
210
60
240
90
270
120
300
150
330
180 0
r = 5
r = 0.1
d = 0.75
Normalized Scattered Field Using BVS and IS
36
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
-30
-20
-10
0
10
20
30
210
60
240
90
270
120
300
150
330
180 0
-30
-20
-10
0
10
20
30
210
60
240
90
270
120
300
150
330
180 0 = 0.041
Co-Polarized
X-Polarized
Dielectric
F. RCSmax_Diel = 18.3 dB
F. RCSmax_Chi_Co = 11.8 dB
F. RCSmax_Chi_X = -1.35 dB
B. RCSmax_Diel = 17 dB
B. RCSmax_Chi_Co = -20 dB
B. RCSmax_Chi_X = -8 dB
r = 5
r = 0.1
d = 0.75
RCS Radiation Pattern in dB Using BVS and IS
37
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
) Parametric Study for a vertical Inhomogeneous Strip
Back-ward Scattered field for different Chiral admittance values
For-ward Scattered field for different Chiral admittance values
2 3 4 5 6 7 8 9 10
x 10-3
-20
-15
-10
-5
0
5
10
15
20
Ba
ckw
ard
-Sca
ttere
r (d
B)
c
Backward-DielectricBackward-Co-PolarizedBackward-X-Polarized
2 3 4 5 6 7 8 9 10
x 10-3
-10
-5
0
5
10
15
20
25
Fo
rwa
rd-S
catte
rer
(dB
)
c
Forward-DielectricForwrd-Co-PolarizedForwrd-X-Polarized
38
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
= 0.00573
Co-Polarized
X-Polarized
Dielectric
F. RCSmax_Diel = 20 dB
F. RCSmax_Chi_Co = 26 dB
F. RCSmax_Chi_X = -5 dB
B. RCSmax_Diel = 15.5 dB
B. RCSmax_Chi_Co = 2 dB
B. RCSmax_Chi_X = -10 dB
RCS Radiation Pattern in dB for a TMz
Plane Wavec = - 0.00573
--- --
c = + 0.00573
c = - 0.00573
c = + 0.00573--
---
---
- --
c = + 0.00573
c = - 0.00573
-40 -30 -20 -10
0 10 20 30
30
210
60
240
90
270
120
300
150
330
180 0
-40 -30
-20 -10
0 10 20
30
30
210
60
240
90
270
120
300
150
330
180 0
39
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
= 0.002445
Co-Polarized
X-Polarized
Dielectric
F. RCSmax_Diel = 20 dB
F. RCSmax_Chi_Co = 25 dB
F. RCSmax_Chi_X = -5 dB
B. RCSmax_Diel = 15.5 dB
B. RCSmax_Chi_Co = 0 dB
B. RCSmax_Chi_X = -10 dB
RCS Radiation Pattern in dB for a TEz
Plane Wavec = - 0.002445
--- --
c = + 0.002445
c = - 0.002445
c = + 0.002445--
---
---
- --
c = + 0.002445
c = - 0.002445
-40 -30 -20 -10
0 10 20 30
30
210
60
240
90
270
120
300
150
330
180 0
-40
-30
-20
-10 0 10 20 30
30
210
60
240
90
270
120
300
150
330
180 0
40
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Conclusions
Techniques are developed for time and frequency domain analysis of chiral material.
Application of chiral material is demonstrated for:
designing anti-reflection composite structures controlling or altering the RCS of scatterers.
41
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
End of Presentation
42
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
0 0.01 0.02 0.03 0.04 0.050
50
100
150
200
250
300
350
Chiral Admittance, c
Ch
iral I
mp
ed
na
ce
Parameters1Parameters2
Intrinsic Impedance and Wave Number Versus Chiral Admittance
0r 0
0
Parameters 1: 2, 3, 1 , 307.812rr d
r
m
21 ( / ) /i i ci i i cik k
2/[ (1 ( / ) )]ci i i i i ci
0r 0
0
Parameters 2: 4, 8, 1 , 266.5736rr d
r
m
0 0.01 0.02 0.03 0.04 0.05-5
0
5
10
15
20
25
30
Chiral Admittance, c
Wa
ve N
um
be
r (d
B)
k +k -k
Parameters 1
43
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
) Parametric Study for a vertical Inhomogeneous Strip
0.05 0.1 0.15 0.2 0.25 0.3
-40
-30
-20
-10
0
10
20
Ba
ckw
ard
-Sca
ttere
r (d
B)
Radius
Backward-DielectricBackward-Co-PolarizedBackward-X-Polarized
Back-ward Scattered field for different Radius values
0.05 0.1 0.15 0.2 0.25 0.3
-40
-30
-20
-10
0
10
20
Fo
rwa
rd-S
catte
rer
(dB
)
Radius
Forward-DielectricForwrd-Co-PolarizedForwrd-X-Polarized
For-ward Scattered field for different Radius values
44
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Bistatic Echo Width of a Circular Chiral Cylinder Illuminated by a TMz Plane Wave
mrmme
rr
1.0,1
,0.0tan, 0.0tan
,0005.0,5.1,4
0
* Majeed A. Al-Kanhal and Ercument Arvas, “Electromagnetic Scattering from a Chiral Cylinder of Arbitrary Cross Section,” IEEE Trans. Antennas Propagate., vol. 44, pp. 1041-1048, July 1996.
0 50 100 150-18
-16
-14
-12
-10
-8
-6
-4
(degrees)
/
0 (
dB)
BVSIter. Soln.MOM* Soln.BVSIter. Soln.MOM* Soln.
CO-POLARIZED ( Ez )
CROSS POLARIZED ( E )
x
y
inczE
45
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
Internal H-field along y = 0 of a Circular Chiral Cylinder Excited by a TEz Wave
0
2 , 3 , 0.002,
0.15 , tan 0.05,
tan 0.05 , 1
r r
e
m
r m
m
-0.1 -0.05 0 0.05 0.1 0.150
0.5
1
1.5
2
2.5
x(m)
|H/H
inc|
BVSIter. Soln.MOM* Soln.BVSIter. Soln.MOM* Soln. 0) (achiral Hz
zHx
y
izH
* Majeed A. Al-Kanhal and Ercument Arvas, “Electromagnetic Scattering from a Chiral Cylinder of Arbitrary Cross Section,” IEEE Trans. Antennas Propagate., vol. 44, pp. 1041-1048, July 1996.
46
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
|Ez| of a TMz Plane Wave within a Homogeneous Dielectric Cylinder
-0.15 -0.1 -0.05 0 0.05 0.1 0.150.4
0.6
0.8
1
1.2
1.4
1.6
x(m)
Ez-m
agni
tude
BVSMOM* Soln.Iter. Soln.
x
y
inczE
A cylinder of circumference 1.0 and r = 3
* Andrew F. Peterson, Scott L. Ray and Raj Mittra, “Computational Methods for Electromagnetics,” IEEE Antennas Propagate.,© 1998 by the Institute of Electrical and Electronics Engineers, Inc.
47
The University of Mississippi Department of Electrical EngineeringC
ente
r of
Ap
pli
ed E
lect
rom
agn
etic
Sys
tem
s R
esea
rch
(C
AE
SR
)
|Hz/Hinc| of a TEz Plane Wave within a Circular, Homogeneous Dielectric Cylinder
-0.15 -0.1 -0.05 0 0.05 0.1 0.15
1.3
1.4
1.5
1.6
Distance along center cut
|Hz/H
inc|
BVSMOM* Soln.Iter. Soln.
y
x
izH
A cylinder of circumference 1.0 and r=2.56
* Andrew F. Peterson, Scott L. Ray and Raj Mittra, “Computational Methods for Electromagnetics,” IEEE Antennas Propagate.,© 1998 by the Institute of Electrical and Electronics Engineers, Inc.