Inter
national
J
our
nal
of
Electrical
and
Computer
Engineering
(IJECE)
V
ol.
8,
No.
4,
August
2018,
pp.
2021
–
2028
ISSN:
2088-8708
2021
I
ns
t
it
u
t
e
o
f
A
d
v
a
nce
d
Eng
ine
e
r
i
ng
a
nd
S
cie
nce
w
w
w
.
i
a
e
s
j
o
u
r
n
a
l
.
c
o
m
A
No
v
el
W
ideband
Bandpass
Filter
using
H-shaped
DGS
V
an-Phuong
Do,
Duy-Manh
Luong,
Chi-Hieu
T
a,
and
Minh-T
an
Doan
Department
of
Radio
Electronic
Engineering,
Le
Quy
Don
T
echnical
Uni
v
ersity
,
Hanoi,
V
ietnam
Article
Inf
o
Article
history:
Recei
v
ed
October
4,
2017
Re
vised
March
14,
2018
Accepted:
April
2,
2018
K
eyw
ord:
Bandpass
filter
defected
ground
structure
DGS
unit
H-shaped
DGS
W
ideband
bandpass
filter
ABSTRA
CT
This
paper
presents
a
no
v
el
compact
wide-band
bandpass
filter
(BPF)
ha
ving
good
se-
lecti
vity
.
It
is
designed
using
a
dual-plane
structure
which
consists
of
a
parallel-coupled
microstrip
line
on
the
upper
surf
ace
and
three
H-shape
defected
ground
structure
(DGS)
on
the
ground
plane.
By
adding
three
H-shape
DGS
units
on
the
ground
plane,
then
properly
adjusting
their
dimensions
and
position,
the
bandwidth
and
selecti
vity
of
the
de-
signed
filter
can
be
significantly
impro
v
ed.
A
com
pact
prototype
of
wide-band
microstrip
bandpass
filter
has
been
designed,
f
abricated
and
measured
to
apply
for
the
wireless
sys-
tems.
The
filter
sho
ws
a
center
frequenc
y
at
4.8
GHz,
passband
from
2.8
GHz
to
6.8
GHz
with
maximum
insertion
loss
and
return
loss
of
0.8
dB
and
40
dB,
respecti
v
ely
.
The
mea-
sured
results
agrees
well
with
the
theoretical
e
xpectations
v
alidating
the
proposed
design.
Copyright
c
2018
Institute
of
Advanced
Engineering
and
Science
.
All
rights
r
eserved.
Corresponding
A
uthor:
Name:
V
an-Phuong
Do
Af
filiation
Address:
236,
Hoang
Quoc
V
iet,
Hanoi,
V
ietnam
Phone:
0995155168
Email:
dvphuongntcity@gmail.com,
phuongdo
v
an@tcu.edu.vn
1.
INTR
ODUCTION
Recently
,
the
microstrip
wide-band
bandpass
filter
(BPF)
with
high
performance
has
become
one
of
the
most
important
circuit
components
in
the
modern
broadband
wireless
communication
systems
[1].
Furthermore,
it
has
recei
v
ed
much
attention
due
to
the
promising
adv
ant
ages
such
as
high
selecti
vity
,
small
size,
lo
w
cost
and
easy
f
abrication.
In
[2],
by
adjusting
dimensions
of
the
meandered
transv
ersal
resonator
and
asymmetrical
interdigital
coupled
lines,
a
wideband
microstrip
BPF
with
good
rejection
in
out
of
the
band
has
been
designed
and
f
abricated.
Ho
we
v
er
,
these
filters
ha
v
e
a
major
disadv
antage
of
lar
ge
size.
In
[3],
another
wide-band
bandpass
filt
er
using
the
folded
multiple-mode
resonator
is
designed.
Ho
we
v
er
,
this
filter
has
a
dra
wback
of
weak
isolation
between
the
input
and
output.
In
[4],
[5]
authors
an
application
of
the
DGS
to
can
signifi
cantly
impro
v
e
the
reflection
coef
ficient
(
S
11
)
of
microstrip
antennas.
F
or
microstri
p
bandpass
filter
design,
In
[6],
[7],
the
complementary
split-
ring
resonator
(CSRR)
is
etched
on
the
ground
plane.
It
is
used
as
the
basic
resonant
unit
to
design
the
wideband
bandpass
filter
with
good
wideband
response.
Ho
we
v
er
,
the
filter
of
this
type
is
either
quite
lar
ge
in
size
or
has
a
comple
x
structure.
In
[8],
the
method
to
design
the
UWB
bandpass
filter
using
a
transmission
line
structure
with
tw
o
embedded
U-s
hape
slots
and
a
dumbbell
shape
DGS
periodic
array
etched
on
the
ground
in
order
to
obtain
the
wide
stopband
ef
fect
b
ut
this
filter
is
sti
ll
b
ulk
y
.
It
has
a
relati
v
ely
lar
ger
size,
up
t
o
24
mm
in
length.
In
[9]
,
a
no
v
el
wideband
bandpass
filters
with
compact
size
and
lo
w
insertion
loss
using
DGS
slots
were
designed
and
analyzed.
In
[10],
an
UWB
BPF
with
high
selecti
vity
w
as
proposed.
Its
design
consists
of
a
high-lo
w
impedance
microstrip
line,
a
short-circuited
stub
combined
with
dif
ferent
DGSs
(H-shape
DGS
slots
and
dumbbell-shape
DGS
slots).
Ho
we
v
er
,
this
type
of
filters
is
also
lar
ge
in
size
with
a
relati
v
ely
complicated
structure.
In
this
paper
,
we
present
a
technical
solution
to
the
abo
v
ementioned
dra
wbacks
of
the
bandpass
filter
by
using
the
H-shaped
DGS
units
for
wide-band
filter
design
with
the
aim
of
impro
ving
its
performance
in
passband
and
stopband
characteristics.
A
no
v
el
compact
wide-band
microstrip
bandpass
filter
using
H-shaped
DGS
using
a
parallel-coupled
microstrip
line
resonator
on
the
upper
surf
ace
combined
with
three
H-shaped
DGS
units
on
the
ground
plane
is
designed
and
f
abricated.
The
theoretical
design,
simulation
and
e
xperimental
results
of
the
filter
are
presented
and
discussed.
J
ournal
Homepage:
http://iaescor
e
.com/journals/inde
x.php/IJECE
I
ns
t
it
u
t
e
o
f
A
d
v
a
nce
d
Eng
ine
e
r
i
ng
a
nd
S
cie
nce
w
w
w
.
i
a
e
s
j
o
u
r
n
a
l
.
c
o
m
,
DOI:
10.11591/ijece.v8i4.pp2021-2028
Evaluation Warning : The document was created with Spire.PDF for Python.
2022
ISSN:
2088-8708
2.
RESON
ANT
PR
OPER
TY
OF
H-SHAPED
DGS
The
DGSs
is
etched
on
the
ground
plane
of
the
pla
n
a
r
filter
,
the
y
disturb
the
shi
eld
current
distrib
ution
on
the
ground
plane
leading
to
the
change
in
characteristics
of
the
resonant
circuit
in
the
upper
plane.
This
structure
can
suppress
the
harmonics,
reduce
the
ph
ysical
dimensions
and
impro
v
e
stopband
and
passband
characteristics
of
the
microstrip
filter
[11].
There
are
man
y
a
v
ailable
DGSs
with
dif
fer
ent
shapes
as
presented
in
[12],
[13].
Where,
the
dumbbell-shaped
DGS
is
structured
v
ery
simply
and
can
be
easily
adjusted
its
geometry
dimensions
to
tune
the
characteristics
of
the
resonance
circuits.
The
structure
of
a
dumbbell-s
haped
DGS
unit
comprises
tw
o
rectangular
etched
defects
with
the
dimensions
of
(
a
b
)
in
backside
metallic
ground
plane.
The
y
are
connected
to
each
other
by
a
narro
w
slot
with
the
dimensions
of
(
g
d
)
as
sho
wn
in
Figure
1(a).
Figure
1.
The
structure
and
the
equi
v
alent
circuit
of
DGS
dumbbell-shaped.
(a)
Structure.
(
b)
Equi
v
alent
circuit
[11].
By
changing
the
geometry
of
the
rectangular
etched
defects,
one
can
change
the
inductance
of
the
dumb-
bell
shaped
DGS
unit
while
changing
the
narro
w
slot
size,
its
capacitance
can
be
v
aried
[14].
Therefore,
the
dumbbell
shaped
DGS
unit
can
be
treated
as
a
parallel
LC
resonant
circuit
as
indicated
in
Figure
1(b).
Its
equi
v
a-
lent
L
and
C
v
alues
are
determined
as
belo
w
.
L
=
1
4
2
f
2
0
C
(1)
C
=
f
C
4
Z
0
(
f
2
0
f
2
C
)
(2)
where,
f
0
is
the
resonant
frequenc
y
of
the
parallel
LC
resonant
circuit,
f
C
is
the
cutof
f
frequenc
y
of
the
prototype
lo
w-pass
filter
and
Z
0
denotes
the
scaled
impedance
of
the
in/out
terminated
ports,
and
is
gi
v
en
by
the
prototype
v
alue
of
the
Butterw
orth
type
lo
w
pass
filter
.
It
is
noted
that,
since
there
is
no
e
xplicit
correlation
between
the
ph
ysical
dimensi
ons
and
the
parameters
of
the
LC
equi
v
alent
circuit,
the
performance
of
the
dumbbell-shaped
DGS
is
only
predictable
through
an
optimization
process.
Applying
promising
propert
ies
of
t
he
dumbbell-shaped
DGS
to
wide-band
BPF
design,
we
propose
a
no
v
el
compact
wide-band
BPF
using
H-shaped
DGSs.
The
detailed
design
process
will
be
presented
in
the
follo
wing
sections.
3.
AN
AL
YSIS
AND
DESIGN
OF
PR
OPOSED
FIL
TER
T
o
design
the
proposed
wide-band
microstrip
bandpass
filter
we
first
design
a
parallel-coupled
microstrip
line
resonator
on
the
upper
plane
as
indicated
in
Figure
2(a).
It
is
composed
of
tw
o
microstrip
transmission-line
sections
w
ork
ed
as
half-w
a
v
elength
resonators.
In
this
case,
the
tw
o
resonant
frequencies
may
be
o
v
erlapped
or
split
depending
on
the
geometrical
conditions
of
the
structure.
The
stronger
coupling
can
be
achie
v
ed
when
narro
wing
the
distance
S
.
The
e
n
e
r
gy
then
will
be
coupled
to
the
output
forming
a
passband,
as
depicted
in
Figure
2(b).
The
dimensions
of
the
parallel-coupled
microstrip
line
resonator
are
set
as
L
1
=
2.1
mm,
L
2
=
9.7
mm,
W
1
=
1.4
mm,
W
2
=
0.6
mm
and
S
=
0.38
mm.
Ho
we
v
er
,
the
distance
S
cannot
be
too
narro
w
and
the
couple
line
cannot
form
transmission
if
S
is
too
lar
ger
.
This
means
there
should
be
an
optimum
v
alue
for
S.
IJECE
V
ol.
8,
No.
4,
August
2018:
2021
–
2028
Evaluation Warning : The document was created with Spire.PDF for Python.
IJECE
ISSN:
2088-8708
2023
(a)
(b)
Figure
2.
Layout
and
response
of
the
wide-band
BPF
without
H-shaped
DGS.
(a)
Layout.
(b)
Frequenc
y
responses.
(a)
(b)
Figure
3.
.
Layout
and
responses
of
the
wide-band
micostrip
BPF
with
a
H-shaped
DGS
unit.
(a)
Layout,
(b)
Frequenc
y
responses.
A
No
vel
W
ideband
Bandpass
F
ilter
using
H-shaped
DGS
(V
an-Phuong
Do)
Evaluation Warning : The document was created with Spire.PDF for Python.
2024
ISSN:
2088-8708
T
o
impro
v
e
the
characteristics
of
parallel-coupled
microstrip
line
resonator
on
the
upper
surf
ace,
we
design
an
additional
H-shaped
DGS
unit
at
the
center
of
the
ground
plane
as
sho
wn
in
Figure
3(a).
The
initial
H-shaped
DGS
model
and
L
,
C
v
alues
are
determined
by
equations
(1)
and
(2).
The
dimensions
of
the
H-shaped
DGS
are
designed
as
a
=
7
mm,
b
=
0.6
mm,
d
=
5
mm,
g
=
0.4
mm
and
c
=
3.3
mm.
Since
the
ener
gy
i
s
coupled
by
the
H-shaped
DGS,
its
resonant
frequenc
y
is
close
to
the
center
frequenc
y
of
the
passband
of
the
parallel-coupled
microstrip
line
resonator
.
The
simulated
results
are
sho
wn
in
Figure
3(b)
which
is
obtained
with
dif
ferent
H-shaped
DGS
locations.
A
position
with
v
alue
of
L
x
=
15
mm,
L
y
=
15
mm
seems
to
be
good
for
S
11
v
S
21
.
Ne
v
ertheless
it
can
be
seen,
from
these
results
that
the
quality
of
such
a
proposed
filter
is
limited
and
not
suf
ficient
for
wireless
telecommuni-
cation
application.
Figure
4.
Layout
of
the
proposed
wide-band
microstrip
BPF
with
three
H-shaped
DGS
units.
T
o
enhance
the
quality
of
the
proposed
filt
er
which
meets
requirements
of
the
wireless
systems,
we
add
tw
o
additional
H-shaped
DGS
units
on
the
ground
plane
as
illustrated
in
Figure
4.
This
addition
will
increase
the
de
gree
of
freedom
of
the
tuned
parameters
for
the
proposed
filter
leading
to
high
possibility
of
perofrmance
impro
v
ement.
As
mentioned
before,
the
resonant
frequenc
y
and
bandwidth
of
the
proposed
filter
can
be
adjusted
easily
by
changing
the
geometric
dimensions
of
three
H-shaped
DGS
units
on
the
ground
plane.
W
e
properly
adjust
the
dimensions
of
three
H-shaped
DGS
unit
s,
then
the
tar
get
resonant
frequenc
y
and
bandwidth
can
be
obtained
as
depicted
in
Figure
5
and
Figure
6,
respecti
v
ely
.
Figure
5
sho
ws
that
when
changing
dimensions
a
and
g
of
the
central
H-shaped
DGS
unit,
desired
prop-
ag
ation
characteristics
of
the
proposed
filter
can
be
achie
v
ed.
a
has
an
significant
ef
fect
on
the
return
loss.
As
the
dimensions
of
a
increases
from
6
mm
to
8
mm,
the
return
loss
v
aries
remarkably
.
A
v
alue
of
a
=
7
mm
should
be
good.
Similarly
,
a
v
alue
of
g
=
0.4
mm
seems
to
be
the
good
for
performance
impro
v
ement.
In
this
case,
the
bandwidth
can
be
slightly
v
aried.
It
is
noted
that
changing
in
dimensions
b
and
d
has
no
remarkable
impact
on
S
11
and
S
21
impro
v
ement
[11].
Besides,
the
bandwidth
also
v
aries
slightly
.
In
addition,
Figure
6
indicates
that,
when
adjusting
the
dimensi
on
s
p
and
m
of
the
tw
o
side
H-shaped
DGS
units
the
desired
S
11
can
be
achie
v
ed.
V
arying
p
and
m
has
an
ef
fect
on
the
return
loss
and
bandwidth.
And
a
pair
v
alue
of
p
=
0.5
mm
and
m
=
7.5
mm
seems
to
be
the
good
for
performance
impro
v
ement.
Changing
in
n
and
o
of
H-shaped
DGS
has
no
ef
fect
on
S
11
and
S
21
impro
v
ement.
Ho
we
v
er
,
in
this
case
the
bandwidth
bandpass
of
the
proposed
filter
gets
de
graded
from
4.15
GHz
to
3.58
GHz
as
sho
wn
in
Figure
7.
From
the
abo
v
e
deep
in
v
estig
ations,
a
set
of
optimized
dimensions
for
the
filter
can
be
realized
as:
the
parallel-coupled
microstrip
line
resonator
on
the
upper
surf
ace
with
L
1
=
2.1
mm,
L
2
=
9.7
mm,
W
1
=
1.4
mm,
W
2
=
0.6
mm,
S
=
0.38
mm;
the
H-shaped
DGS
units
at
cent
er
on
the
ground
plane
with
a
=
7
mm,
b
=
0.6
mm,
d
=
5
mm,
g
=
0.4
mm
and
c
=
3.3
mm;
and
tw
o
horizontal
H-shaped
DGS
units
on
the
ground
plane
with
m
=
7.5
mm,
n
=
0.5
mm,
o
=
2.3
mm
and
p
=
0.5
mm.
Such
a
filter
e
xhibits
a
passband
center
frequenc
y
of
4.93
GHz,
passband
bandwidth
of
72.6
%
(from
3.14
GHz
to
6.72
GHz);
within
the
passband,
the
insertion
loss
is
less
than
0.68
dB
while
the
return
loss
is
better
than
31.5
dB.
This
superior
performance
of
the
designed
wide-band
bandpass
filter
with
three
H-shape
DGS
units
IJECE
V
ol.
8,
No.
4,
August
2018:
2021
–
2028
Evaluation Warning : The document was created with Spire.PDF for Python.
IJECE
ISSN:
2088-8708
2025
(a)
(b)
Figure
5.
Simulated
frequenc
y
responses
of
the
proposed
wide-band
microstrip
BPF
with
dif
ferent
a
and
g
.
The
dimensions
of
the
center
H-shaped
DGS
unit
are
a
=
7
mm,
b
=
0.6
mm,
d
=
5
mm
and
g
=
0.4
mm.
(a)
(b)
Figure
6.
Simulated
frequenc
y
responses
of
the
proposed
wide-band
microstrip
BPF
with
dif
ferent
p
and
m
.
The
dimensions
of
the
upper
and
lo
wer
H-shaped
DGS
unit
are
m
=
7.5
mm,
n
=
0.5
mm,
o
=
2.3
mm
and
p
=
0.5
mm.
A
No
vel
W
ideband
Bandpass
F
ilter
using
H-shaped
DGS
(V
an-Phuong
Do)
Evaluation Warning : The document was created with Spire.PDF for Python.
2026
ISSN:
2088-8708
Figure
7.
Simulated
frequenc
y
responses
of
the
proposed
wide-band
microstrip
BPF
.
compared
to
the
pre
viously
filter
without
DGS
demonstrates
v
alidity
of
the
proposed
design
(especially
in
terms
of
the
insertion
loss,
the
passband
ripple
and
the
3
dB
bandwidth).
4.
F
ABRICA
TION
OF
THE
PR
OPOSED
FIL
TER
AND
DISCUSS
One
prototype
of
the
proposed
wide-band
microstrip
bandpass
filter
using
H-shaped
DGS
has
been
de-
signed
and
f
abricated
on
a
substrate
R
O
4350
with
"
r
=
3.66
and
h
=
0.762
mm.
(a)
(b)
Figure
8.
Photograph
of
the
proposed
wide-band
microtrip
BPF
.
(a)
T
op
vie
w
.
(b)
Bottom
vie
w
.
The
f
abricated
filter
photograph
is
sho
wn
in
Figure
8,
the
size
of
the
filter
is
(18
7.8)
mm
which
is
quite
compact.
The
measured
results
of
the
f
abricated
filter
are
sho
wn
in
Figure
9,
where
good
agreement
between
the
simulation
and
measurement
can
be
clearly
observ
ed.
The
measured
3
dB
fractional
bandwidth
of
the
f
abricated
filter
achie
v
es
83.3
%
(2.8
-
6.8)
GHz.
The
center
frequenc
y
is
4.8
GHz.
The
maximum
passband
insertion
loss
is
0.8
dB
and
the
maximum
return
loss
is
40
dB.
This
measured
performance
is
v
ery
promising
for
the
wireless
communications
application.
The
small
de
viations
between
the
simulated
and
measured
results
is
considered
due
to
our
poor
soldering
craft
and
error
in
f
abrication
or
measurement
system.
5.
CONCLUSION
This
paper
presents
a
no
v
el
technical
solution
for
impro
v
ement
of
wide-band
bandpass
filter
performance
in
the
stopband
and
passband
by
using
the
H-shaped
DGS
units.
A
compact
wide-band
microstrip
BPF
using
parallel-coupled
microstrip
line
resonator
and
three
H-shape
DGS
units
has
been
designed
and
f
abricated.
The
measured
results
sho
w
that
the
filter
w
orks
well
at
the
frequenc
y
r
ange
of
2.8
GHz
to
6.8
GHz.
The
maximum
IJECE
V
ol.
8,
No.
4,
August
2018:
2021
–
2028
Evaluation Warning : The document was created with Spire.PDF for Python.
IJECE
ISSN:
2088-8708
2027
fig_WB/S11-21_mp-do_3xog_PDF.pdf
Figure
9.
Simulated
and
measured
responses
of
the
proposed
wide-band
microstrip
BPF
.
passband
insertion
loss
is
0.8
dB
and
the
maximum
return
loss
is
40
dB.
Therefore,
the
filter
fits
well
for
v
arious
wireless
communication
systems
such
as
micro
w
a
v
e
Access
(W
iMAX)
at
3.5
GHz,
INSA
T
C-band
at
4.6
GHz,
W
ireless
Local
Area
Netw
ork
(WLAN)
at
5.6
GHz
applications.
V
ery
good
agreement
between
simulations
and
measurements
demonstrates
v
alidity
of
the
prosed
design
strate
gies.
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u,
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el
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Y
ang,
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ang,
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el
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ang,
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ittoria,
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.
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ireless
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ark,
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.
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.
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w-pass
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v
el
microstrip
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”
IEEE
T
ran.
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w
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C.
Gar
g
and
M.
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”A
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vie
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w
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v
e
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”
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ati
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A.
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umar
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yan,
”Design
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w
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679-686,
2017.
[14]
A.
K
umar
and
M.
Kartik
e
yan,
”Design
and
realization
of
microstrip
filters
with
ne
w
defected
ground
structure
(DGS),
”
Engineering
Science
and
T
echnology
,
an
International
Journal
,
v
ol.
20,
pp.
679-686,
2017.
A
No
vel
W
ideband
Bandpass
F
ilter
using
H-shaped
DGS
(V
an-Phuong
Do)
Evaluation Warning : The document was created with Spire.PDF for Python.
2028
ISSN:
2088-8708
BIOGRAPHIES
OF
A
UTHORS
V
an-Phuong
Do
graduated
Colle
ge
specialized
T
elecommunications
engineering
from
T
elecom-
munication
Uni
v
ersity
,
Nhatrang,
Khanhhoa,
V
ietnam,
in
1996.
He
recei
v
ed
the
B.Eng
and
M.Eng
de
grees
in
Radio
Elictronic
Engineering
from
Le
Qui
Don
T
echnical
Uni
v
ersity
,
Hanoi,
V
ietnam
in
2000
and
2003,
respecti
v
ely
.
He
is
currently
a
teacher
and
pursuing
the
Ph.D.
de
gree
in
elec-
tronic
engineering
at
Le
Quy
Don
T
echnical
Uni
v
ersity
,
Hanoi.
His
research
interest
includes
the
technique
of
electronic,
fundamental
study
of
micro
w
a
v
e
technical
and
design
of
micro
w
a
v
e
filter
.
E-mail:
dvphuongntcity@gmail.com;
phuongdo
v
an@tcu.edu.vn
Duy-Manh
Luong
recei
v
ed
the
B.S.
and
M.S.
de
grees
in
ph
ysics
from
Hanoi
Uni
v
ersity
of
Sci-
ence
(HUS),
a
member
of
V
ietnam
National.
Uni
v
ersity
(VNU),
Hanoi,
V
iet
nam,
in
2005
and
2007,
respecti
v
ely
,
and
the
D.E.
de
gree
in
electronics
engineering
from
the
Uni
v
ersity
of
Electro-
Communications
(UEC),
T
ok
yo,
Japan,
in
March
2016.
He
is
currently
a
specially
appointed
researcher
at
Graduate
School
of
Engineering
Science,
Osaka
Uni
v
ersity
,
Japan.
His
research
interests
include
de
v
elopment
of
micro
w
a
v
e
semiconductor
de
vices
and
circuits
and
millimeter
-
w
a
v
e
(mm
W)
systems
for
wireless
communication
applications
based
on
resonant
tunneling
diodes
(R
TDs)
and
photonic
crystals.
Chi-Hieu
T
a
w
as
born
in
V
inh
Phuc
in
1970.
He
graduated
the
Military
T
echnical
Academy
in
1994
with
hornor
.
He
got
his
MSc
de
gree
in
electronic
engineering
in
the
National
Defense
Academy
of
Japan
in
2002
and
his
PhD
de
gree
in
signal
processing
in
the
Uni
v
ersity
of
Strathclyde,
United
Kingdom
in
2008.
He
is
currently
w
orking
at
the
F
aculty
of
Radio
Electroni
cs,
Military
T
echnical
Academy
.
His
research
interests
include
precoding
and
equalization
for
MIMO
systems,
micro
w
a
v
e
engineering
and
computational
electromagnetics.
Minh-T
an
Doan
recei
v
ed
the
B.Eng
and
M.Eng
de
grees
in
Radio
Elictronic
Engineering
from
Le
Qui
Don
T
echnical
Uni
v
ersity
,
Hanoi,
V
ietnam
in
2000
and
2003,
respecti
v
ely
,
Ph.D.
de
gree
in
Department
of
Communication
Engineering
Nanjing
Uni
v
ersity
of
Science
and
T
echnology
,
Nan-
jing,
China
in
2012,
He
is
currently
a
lecturer
of
F
aculty
of
Radio-Electronics
Engineering,
Le
Qui
Don
T
echnical
Uni
v
ersity
,
Hanoi.
His
research
interests
include
the
design
of
micro
w
a
v
e
filter
and
associated
RF
modules
for
micro
w
a
v
e
and
signal
processing
for
communication.
IJECE
V
ol.
8,
No.
4,
August
2018:
2021
–
2028
Evaluation Warning : The document was created with Spire.PDF for Python.