Indonesian Journal of
Electrical
Engineer
ing and
Computer Science
V
o
l. 10
, No
. 3, Jun
e
20
18
, pp
. 91
7
~
92
4
ISSN: 2502-4752,
DOI: 10.
11591/ij
eecs.v10
.i3.pp917-924
9
17
Jo
urn
a
l
h
o
me
pa
ge
: http://iaescore.c
om/jo
urnals/index.php/ijeecs
Structural Health Monitoring
Sensor based on a Flexible
Microstrip Patch Antenna
Hamse
Abdillahi Haji Ome
r
, Said
atul Norlyana Az
emi,
Az
remi
Abdullah
Al
-Hadi, Ping Jack Soh,
Mo
hd Fai
z
al
Ja
ml
os
Advanced Com
m
unication
Engineering
Centr
e
(
A
CE) CoE,
Sch
ool of Computer
and Communication
Engin
eer
in
g,
Universiti Malaysia Pe
rlis (UniMAP), Pauh Putra, Arau 02600
, M
a
lay
s
ia.
Article Info
A
B
STRAC
T
Article histo
r
y:
Received
Ja
n 15, 2018
Rev
i
sed
Mar
12
, 20
18
Accepted
Mar 28, 2018
A m
i
crostrip p
a
tch
ant
e
nna
st
rain
sensor op
erating
at dual
frequencies
1.8GHz and 2
.
4
GHz have b
een
desi
gned b
a
sed
on the relation
between
the
resonant fr
equen
c
y
and
the str
a
in
applied
to
it
. Fe
lt substrat
e with
a heigh
t
of
3mm and dielectric constan
t
of
1.44
and
shield
conductor
ar
e u
s
ed for th
e
design of this antenna. Testing
results
show that the r
e
sonant fr
equency
o
f
the m
i
crostr
ip pa
tch
antenn
a is 1
.
78 GHz
and 2
.
4
GHz, which
agrees with th
e
simulation. The resonant
fr
equen
c
y
of
the
m
i
crostrip pa
tch
antenn
a incr
ease
s
line
a
rl
y wi
th th
e
incr
ease of
th
e
appli
e
d
stra
in.
T
h
is m
i
crostrip p
a
tch
antenn
a
strain sensor can
be integr
ated with
other compon
ents easily
and h
a
ve a great
potential applications
in
structur
al hea
lth
m
onitori
ng s
y
st
em
s.
K
eyw
ords
:
Flex
ib
le An
tenn
a
M
oni
nt
ori
n
g
Pat
c
h Ant
e
nna
SHM
Strain Sens
or
Copyright ©
201
8 Institut
e
o
f
Ad
vanced
Engin
eer
ing and S
c
i
e
nce.
All rights re
se
rve
d
.
Co
rresp
ond
i
ng
Autho
r
:
Mohd Faizal J
a
m
l
os,
Sch
ool
o
f
C
o
m
put
e
r
a
n
d
C
o
m
m
uni
cat
i
on En
gi
nee
r
i
n
g,
Un
i
v
ersiti Malaysia Perlis (Un
i
MAP),
Pauh
Pu
tr
a, A
r
au
0
260
0,
Mal
a
ysia.
1.
INTRODUCTION
During
the pas
t
few
de
cades there have bee
n
sign
ifican
t
dev
e
lop
m
en
t in
civ
il in
d
u
stries, aero
s
p
ace
and m
a
ri
nes.
These a
d
vance
s
i
n
cl
u
d
e n
e
w
m
a
nufact
uri
n
g t
ech
ni
q
u
es,
new c
o
m
p
o
n
e
n
t
s
,
devi
ces
re
l
a
t
e
d t
o
com
putational soft
ware
a
n
d new design
proc
ess.
At the si
de
of aeros
pace
one
of t
h
e m
a
in devel
opm
ents is the
usa
g
e o
f
hi
g
h
l
y
adva
nce
d
co
m
posi
t
e
m
a
t
e
rial
s and
w
h
e
n
we c
o
m
p
are these m
a
terial with the ot
her material
use
d
for aeros
pace, they
have a lot of adva
ntages
, like good electrom
a
gnetic pr
operties whic
h m
a
kes them
ap
p
licab
le fo
r
m
u
l
tifu
n
c
tion
a
l ap
p
lication
s
i
n
b
o
t
h
m
ili
tary
aircrafts and
co
mmercial [1
].
On
t
h
e o
t
h
e
r
han
d
co
m
p
o
s
ite
m
a
terials h
a
v
e
in
trodu
ced
new co
m
p
lex
ity in
h
ealth
an
d
m
o
n
ito
ring
m
a
nagem
e
nt
for
ci
vi
l
st
r
u
ct
u
r
es, m
a
ri
ne a
n
d ae
ros
p
ace
. T
h
ese
dra
w
bac
k
s a
r
e
new
f
o
r
m
of dest
r
u
ct
i
o
n
s
u
c
h
as fi
bre
dam
a
ge, del
a
m
i
nat
i
o
n an
d de
bo
ni
n
g
w
h
i
c
h i
m
pro
v
ed t
h
e
nee
d
f
o
r t
r
ust
w
ort
h
y
and pe
rfe
ct
d
a
m
a
ge
m
oni
t
o
ri
ng t
e
c
hni
que
. St
r
u
ct
ural
heal
t
h
m
oni
t
o
ri
ng i
s
a
n
e
w t
ech
n
o
l
o
gy
whi
c
h
pr
ovi
d
e
s sy
st
em
s t
h
at
are
capabl
e
o
f
c
o
nst
a
nt
l
y
m
oni
t
o
ri
ng
st
r
u
ct
u
r
e
s
f
o
r
dam
a
ge
wi
t
h
m
i
nim
a
l
hum
an m
e
di
at
ion
.
St
ruct
ural
heal
t
h
m
o
n
ito
rin
g
are th
eir in
itial p
h
a
ses
o
f
im
p
r
o
v
e
m
e
n
t
an
d
req
u
i
re adv
a
n
c
ed
techn
o
l
o
g
y
to
u
s
e th
em
i
n
real
structure [2]. The obj
ecti
v
e
of structural health m
onitori
ng syst
em
s is
to
dec
r
ease
maintenance c
o
sts,
t
o
redu
ce
ov
erall
o
f
own
e
rsh
i
p of a
v
e
h
i
cle, at t
h
e sam
e
ti
m
e
d
e
v
e
lop
i
ng
safet
y
and
reliab
ilit
y. Th
e
d
e
v
e
l
o
pmen
t
of sa
fety is strong m
o
tivation in
st
ruct
ural health
m
o
nitoring, es
peci
ally after several accidents
happe
n
because
of [3]: 1. Ins
u
fficient
m
a
inte
nance,
for e
x
am
ple at side
of aerona
u
tic
which
is flight related fie
l
d
see
Fi
gu
re 1
or t
h
e col
l
a
pse
of
M
i
anus R
i
ve
r B
r
i
d
ge at
si
de o
f
ci
vi
l
en
gi
nee
r
i
n
g fi
el
d.
2. Oi
l
-
c
o
nt
rol
l
e
d
pr
o
duct
i
o
n p
r
o
cess, fo
r exam
pl
e, t
h
e In
ja
k bri
dge col
l
a
ps
e see Figure 1(b). In both fi
elds the obstacles of
agi
n
g st
r
u
ct
u
r
e
s
was
ex
p
o
se
d
and
s
ubse
q
uent
p
r
o
g
ram
s
wer
e
rec
o
g
n
i
zed
a
n
d
est
a
bl
i
s
he
d.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
502
-47
52
I
ndo
n
e
sian
J Elec Eng
& Com
p
Sci, V
o
l. 10
,
No
.
3
,
Jun
e
2
018
:
91
7 – 92
4
91
8
Although t
h
ere
are a lot of
works a
nd
resea
r
ches t
h
at has
been
done i
n
wireless se
ns
ors and thei
r
ap
p
lication
in
stru
ctural h
ealt
h
m
o
n
ito
ring
,
all th
ese tech
no
log
i
es still h
a
v
e
roo
m
fo
r i
m
p
r
o
v
e
m
e
n
t
. Th
ese
di
sad
v
a
n
t
a
ges
i
n
cl
ude al
l
t
h
e
s
e sy
st
em
s requi
re a bat
t
e
ry
whic
h has a
restricted life time, require se
nsors
whic
h are i
nde
pende
n
t from
each ot
her a
nd also re
qui
re
a
n
tenna that inc
r
eases the
c
o
mplexity, size of the
sens
or
u
n
i
t
,
a
n
d
wei
g
ht
.
It
i
s
al
so c
o
st
l
y
bec
a
use t
h
ey
re
quire s
p
ecial skill
s to
fa
bricate t
h
e se
ns
or, a
n
d
finally
req
u
i
r
e f
o
r a wi
rel
e
ss se
nso
r
net
w
o
r
k
whi
c
h nee
d
c
o
m
p
l
e
x so
ft
ware a
nd
dat
a
acq
ui
si
t
i
on u
n
i
t
s
(
D
A
Q
)
.
M
o
st
l
y
, al
l
t
h
e
m
e
t
hods m
e
nt
i
one
d a
b
o
v
e i
s
a wi
red se
ns
or
s. These se
ns
or
s have m
a
ny
di
sad
v
ant
a
ges su
ch a
s
th
e n
e
ed
fo
r installatio
n
du
ri
ng
b
u
ild
i
n
g.
Wi
res also
limit t
h
e stru
ctures’ fu
n
c
tion
a
lity, ad
d m
o
re co
m
p
lex
ity
to it and inc
r
ease the
heavi
n
ess
of
the st
ruct
ure. There
f
ore, a
ne
w
de
sig
n
of
techno
log
i
es is beco
m
i
n
g
necessa
ry
f
o
r
c
i
vil structu
r
al
h
ealth m
onitorin
g
(SHM
)[
4-
8]
.
The
goal of t
h
is project is to inve
stigate and a
n
al
yses the
effecti
v
enes
s
of a
wireless s
t
rain se
ns
or
u
s
ing
rectang
u
lar Micro
s
tri
p
p
a
tch
an
tenn
as. Utilizin
g
Mi
cro
s
t
r
ip
p
a
tch
an
tenn
a is a
n
e
w techno
log
i
es wh
ich
el
im
i
n
at
es com
p
l
e
x wi
ri
ng net
w
or
ks i
n
st
ruct
ural
heal
t
h
m
oni
t
o
ri
n
g
sy
st
em
and bec
o
m
e
s a new area
o
f
researc
h
.
Figure 1 s
h
ows
Spectacular acc
idents
have m
o
tiv
ated
t
h
e co
mm
u
n
ity to
i
m
p
r
ov
e safet
y
[9
].
Fi
gu
re
2 s
h
ow
s t
h
e c
o
ncept
of
wi
rel
e
ss
S
H
M
se
nso
r
s
u
s
i
n
g
a m
i
crost
r
i
p
pat
c
h
ant
e
nna
. T
h
e
p
r
i
n
c
i
pl
e
o
f
wi
rel
e
ss S
H
M
sens
ors
usi
n
g
m
i
crost
r
i
p
pat
c
h ant
e
n
n
a i
s
base
d o
n
t
h
e
r
e
so
nance
fre
q
u
e
ncy
shi
f
t
as
so
ci
at
ed
with
th
e strai
n
ap
p
lied to
t
h
e
b
u
ild
i
n
g.
(a
)
(b)
Fig
u
re 1
.
(a)
Th
e Aloh
a Airlin
es flig
h
t
24
3, (b)
th
e
Inj
a
k
a
bridg
e
co
llap
s
e, Ju
ly
199
8
Fi
gu
re
2.
C
o
nc
ept
m
i
crost
r
i
p
pat
c
h
base
d
wi
rel
e
ss st
r
u
ct
u
r
a
l
heal
t
h
m
oni
t
o
ri
n
g
se
ns
or
Resonant
fr
equency
shifts
when strain is
applied to
building
Evaluation Warning : The document was created with Spire.PDF for Python.
In
d
onesi
a
n
J
E
l
ec En
g &
C
o
m
p
Sci
ISS
N
:
2
5
0
2
-
47
52
St
ruct
ural
He
a
l
t
h
Mo
ni
t
o
ri
n
g
Sen
s
or
b
a
se
d o
n
a
Fl
exi
bl
e Mi
crost
r
i
p
…
(
H
a
m
se
A
b
di
l
l
ahi
Haj
i
Omer)
91
9
2.
FLE
X
IBLE
MICROSTRIP PAT
C
H ANTEN
NA DESIGN AND
DE
VELOPMENT
The m
o
st im
portant pa
ram
e
ter
s
that need to s
p
ecify
t
o
desi
g
n
M
i
crost
r
i
p
p
a
tch antenna are, antenna
fre
que
ncy
o
f
ope
rat
i
o
n(
fc
), perm
ittivity or dielectric constant of the s
ubst
r
ate(
ε
r
),t
h
i
c
kne
ss o
r
hei
ght
o
f
dielectric subst
r
ate(
h
), a
nd
he
i
ght
o
f
t
h
e co
n
duct
o
r
(
t
).
Ot
he
r par
a
m
e
t
e
rs incl
u
d
e t
h
e wi
d
t
h of t
h
e
pat
c
h
(
w
),
l
e
ngt
h
o
f
t
h
e
pat
c
h,
an
d
wi
d
t
h an
d l
e
n
g
t
h
of t
h
e g
r
ou
n
d
pl
ane a
n
d su
b
s
t
r
at
e (
Ws
an
d
Wg
).
In
th
is p
r
oj
ect
Micro
s
trip
p
a
t
c
h
an
ten
n
a as a strain
sen
s
o
r
will b
e
d
e
sig
n
e
d
.
Th
e o
b
j
ectiv
e
is
frequ
e
n
c
y o
f
t
h
is an
tenn
a
sh
ou
l
d
sh
ift acco
rd
ing
t
o
t
h
e app
lied
strai
n
.
In
th
is
pro
j
ect a felt
will b
e
u
s
ed as a
su
bstrate
wh
ich
h
a
v
e
perm
i
t
t
i
v
i
t
y
of
1.
4
4
a
n
d
hei
ght
o
f
3 m
m
and
s
h
i
e
l
d
as
a co
n
duct
o
r
w
h
i
c
h
has
T
h
i
c
kne
ss:
0
.
1
7
m
m
and
Co
ndu
ctiv
ity = 1
.
18
x
1
0
5
. Ta
ble 1 tabulated
the ante
nna
de
sign speci
fication.
In th
is
d
e
sign
,
th
e du
al-b
an
d tex
tile an
tenn
a
can
d
i
d
a
te was selected
to
b
e
an
E-sh
ap
ed
patch
an
tenn
a
An
E-sh
ap
ed
patch
an
tenn
a is easily fo
rm
ed
b
y
cu
ttin
g
t
w
o
slo
t
s fro
m
a
rectang
u
l
ar shap
e. By cu
tting
th
ese
slo
t
s fro
m
a p
a
tch
th
e d
e
sired
freq
u
e
n
c
y will b
e
ach
iev
e
d
easily [3
], g
a
in
, retu
rn
lo
ss and
b
a
ndwid
th
o
f
micro
-
st
ri
p ant
e
nna c
a
n be i
m
prove
d al
so. T
h
e p
r
o
pos
ed a
n
t
e
n
n
a i
s
desi
gne
d f
o
r
1.8
GHz a
n
d 2.
4G
Hz f
r
eq
ue
nci
e
s
.
Th
e felt and
shield
m
a
terials
are u
s
ed
for con
d
u
c
ting
elemen
ts en
ab
le th
e an
tenn
a to
b
e
flex
ib
le, l
o
w
profile
and l
i
g
ht
wei
g
h
t
. To desi
g
n
d
u
a
l
band a
n
t
e
n
n
a
fi
rst
of al
l
we
cal
cul
a
t
e
d t
h
e param
e
t
e
rs for
si
ngl
e ba
n
d
ant
e
nna
an
d th
en
cu
t t
h
e slo
t
s
o
f
ap
pro
p
riate leng
th
at app
r
o
p
riate
p
o
s
ition
t
o
m
a
k
e
it
d
u
a
l
b
a
nd. In
ou
r d
e
sign firstl
y
we calcu
late the p
a
ram
e
ters of th
e m
i
cro
s
trip
p
a
tch an
te
nn
a t
o
res
onat
e
at
2.
4
GHz
by
usi
n
g
t
h
e
eq
uat
i
o
ns
1-
6
t
a
ki
ng
hei
ght
of
s
ubst
r
at
e
(
h
)=3mm
and dielectric constant
(
ε
r
)=
1.44 T
h
e calc
u
lated
param
e
te
rs are
su
mm
arized
in
Tab
l
e 2
,
After g
e
ttin
g
th
e
d
e
sired
sim
u
la
ted
resu
lts fo
r
2
.
4GHz
freq
u
en
cy, we wen
t
for
cu
ttin
g
slo
t
in
th
e
p
a
tch
to
m
a
k
e
it reso
nate at ano
t
her freq
u
e
n
c
y also
. Before
g
e
ttin
g
the op
tim
u
m
si
m
u
lated
resu
lts
i
n
t
e
rm
s of r
e
t
u
r
n
l
o
ss
, res
ona
nt
f
r
eq
ue
n
c
i
e
s, ba
nd
wi
dt
h an
d i
m
pedance m
a
t
c
hi
ng
we ha
ve
do
ne t
h
e
param
e
t
r
i
c
sim
u
l
a
t
i
on
st
u
d
y
o
f
t
h
e
desi
gne
d
ant
e
n
n
as
[4
-
5
]
.
St
ep 1.
C
a
l
c
ul
at
i
on of
t
h
e wi
dt
h (
W):
(1)
St
ep
2:
C
a
l
c
ul
a
t
i
on
of
ef
fect
i
v
e di
el
ect
ri
c co
n
s
t
a
nt
:
usi
n
g e
q
uat
i
on:
(2)
Step
3
:
Calcu
l
atio
n
o
f
th
e effectiv
e leng
th
(
L
eff
):
eq
uat
i
o
n
3
gi
ve
s t
h
e
ef
fec
t
i
v
e l
e
ngt
h as:
(3)
St
ep
4:
C
a
l
c
ul
a
t
i
on
of
t
h
e l
e
ng
t
h
ext
e
nsi
o
n
(
Δ
L)
:
(4)
St
ep
5:
C
a
l
c
ul
a
t
i
on
of
t
h
e act
u
a
l
l
e
ngt
h
o
f
t
h
e
pat
c
h
(
L
):
(5)
St
ep 6:
C
a
l
c
ul
a
t
i
on of
t
h
e gr
o
u
n
d
pl
ane
di
m
e
nsi
o
ns (L
g
a
n
d Wg
):
(6)
The
geom
et
ry
of t
h
e pat
c
h a
n
t
e
n
n
a f
o
r
d
u
a
l
-ba
nd
o
p
erat
i
on i
s
s
h
ow
n i
n
Fi
g
u
r
e 3
.
T
w
o sl
ot
s are
et
ched
out
fr
o
m
t
h
e pat
c
h t
o
achi
e
ve t
h
e d
u
al
ba
nd
o
p
era
t
i
on. T
h
ese sl
o
t
s
m
a
ke t
h
e pa
t
c
h t
o
bec
o
m
e
and
E-
sha
p
ed
m
i
crost
r
i
p
pat
c
h a
n
t
e
nna
w
o
rki
n
g
wi
t
h
d
u
al
f
r
e
que
nci
e
s.
T
h
e et
chi
n
g
of
sl
ot
s l
eads
t
o
m
a
n
y
2
21
rr
C
W
f
1
2
11
[1
1
2
]
22
rr
ref
f
h
w
2
ef
f
or
e
f
f
c
L
f
0.3
)
(
0
.26
4
)
0.412
(0
.
2
5
8
)
(
0
.
8
)
ref
f
ref
f
W
h
Lh
w
h
2
ef
f
L
LL
6
6
(
3
)
24.26
52.36
6
6
(3
)
66.58
94.58
gb
gb
L
h
L
mm
mm
mm
Wh
W
m
m
m
m
m
m
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
502
-47
52
I
ndo
n
e
sian
J Elec Eng
& Com
p
Sci, V
o
l. 10
,
No
.
3
,
Jun
e
2
018
:
91
7 – 92
4
92
0
param
e
t
e
rs t
o
be e
x
am
i
n
ed f
o
r
d
u
al
-
b
an
d
o
p
erat
i
o
ns.
S
h
i
e
l
d
co
n
duct
o
r
w
h
i
c
h
has T
h
i
c
k
n
ess
of
0.
1
7
m
m
and
Co
ndu
ctiv
ity of 1.18
x
10
5
An
d Felt sub
s
trate is u
s
ed
to
de
si
gn
t
h
i
s
a
n
t
e
n
n
a wi
t
h
di
el
ect
ri
c
co
nst
a
nt
1.
44
an
d
t
h
i
c
kne
ss of
3
m
m
.
The
m
a
t
e
r
i
al
s used fo
r fa
bri
cat
i
o
n of t
h
e ant
e
nna i
s
sh
i
e
l
d
con
duct
o
r
of hei
ght
o
f
0
.
17m
m
wi
t
h
fel
t
su
bs
t
r
at
e of
di
el
ect
ri
c const
a
nt
1.
44 a
n
d t
h
i
c
kne
ss o
f
3m
m
t
h
e fr
o
n
t
vi
e
w
an
d
back
v
i
ew o
f
fab
r
i
cat
ed a
n
t
e
nna
i
s
s
h
o
w
n i
n
Fi
gu
re
4.
Table 1. Design
s
p
ecifications
F
e
a
t
ur
e V
a
l
u
e
Oper
ating Fr
equency
,
f
2.45GHz
Ef
f
i
ciency
More than 50%
Radiating patter
n
Dir
ectional
Dir
ectivity
and gain
M
oder
a
te
Physical profile
Low
pr
ofile and com
p
act
Substrate Felt
T
h
ickness: 3
m
m
Perm
i
ttivity =
1.44
Conduct
o
r
Shielded
T
h
ickness: 0.
17
m
m
Conductivity
= 1.
18 x 10
5
Fi
gu
re
3.
Ge
o
m
et
ry
of E
-
S
h
a
p
e
Ant
e
nna
Tabl
e
2. C
a
l
c
ul
at
ed pa
ram
e
t
e
rs
Para
m
e
ters
Value
(
m
m
)
L
1
28.
2
W
1
18.
5
W
2
10.
85
W
3
18.
5
W
4
16.
85
W
5
24
W
q
w
8.
5
L
qw
23.
5
S
3
30
(a)
(b
)
Fi
gu
re 4.
Fa
bri
cat
ed
E-
Sha
p
e
d
Ant
e
nna
, (a) t
h
e
F
r
o
n
t
Vi
ew of E
-
Shape
antenna, (b)
the rear view of
E-Sha
p
e
an
tenn
a sho
w
i
n
g th
e
Gr
oun
d
p
l
an
e
Evaluation Warning : The document was created with Spire.PDF for Python.
In
d
onesi
a
n
J
E
l
ec En
g &
C
o
m
p
Sci
ISS
N
:
2
5
0
2
-
47
52
St
ruct
ural
He
a
l
t
h
Mo
ni
t
o
ri
n
g
Sen
s
or
b
a
se
d o
n
a
Fl
exi
bl
e Mi
crost
r
i
p
…
(
H
a
m
se
A
b
di
l
l
ahi
Haj
i
Omer)
92
1
3.
R
E
SU
LTS AN
D ANA
LY
SIS
3.1.
E-Shape
Ante
nna S-P
a
rameter
results
The S
-
pa
ram
e
ter pl
ot
s
h
o
w
s t
h
e va
ri
at
i
on
of
ret
u
r
n
l
o
ss
(i
n
dB
)
ove
r a ra
n
g
e o
f
f
r
eq
ue
nci
e
s. Si
nce at
reso
na
nce t
h
e
ant
e
n
n
a i
s
ha
v
i
ng t
h
e
best
i
m
pedance m
a
tchi
n
g
s
o
t
h
e r
e
t
u
r
n
l
o
ss
w
o
u
l
d be m
i
nim
u
m
.
The
desi
g
n
e
d
ant
e
n
n
a res
o
nat
e
s at
1.
8G a
n
d 2
.
4
r
e
spect
i
v
el
y
.
T
h
e ret
u
r
n
l
o
ss o
f
1.
8 G
H
z i
s
-
1
2.
9dB
a
n
d t
h
e
ret
u
r
n
l
o
ss
of
2.
4
G
H
z
i
s
-
2
2
d
B
.
W
h
i
c
h c
o
vers
t
h
e m
i
nim
u
m
requi
red
val
u
e
o
f
ret
u
r
n
l
o
ss
of
-1
0
d
b
,
t
h
e b
a
nd
wi
dt
h
co
v
e
r
e
d
af
ter
fir
s
t and
seco
nd
b
a
nd
ar
e 60MH
z
and
18
0MH
z
r
e
sp
ectively. Th
e
p
l
o
t
fo
r
r
e
tur
n
lo
ss i
s
found
in
Figur
e 5
.
M
easurem
ent
resul
t
dr
ops al
m
o
st at
1.8G
H
z
and 2.
4
5
G
H
z
, whi
l
e
sim
u
l
a
t
i
on act
ual
res
u
l
t
i
s
1.8G
Hz
an
d 2.4GH
z
.
I
t
sho
w
s th
at t
h
e m
easu
r
ed
v
a
lue o
f
r
e
t
u
rn
loss is -1
4.9d
B
f
o
r
lo
w
e
r
fr
eq
u
e
n
c
y b
a
nd
and
-34.2d
B
fo
r
hi
g
h
er
f
r
e
q
uency
ba
n
d
wh
ereas t
h
e si
m
u
l
a
t
e
d
val
u
e
o
f
r
e
t
u
r
n
l
o
ss i
s
-
1
3.
12
dB
a
n
d
-2
.
3
5
d
B
fo
r l
o
we
r a
nd
h
i
gh
er
f
r
e
q
u
e
ncy b
a
nd
r
e
sp
ectiv
ely. Fr
o
m
th
e r
e
su
lt w
e
ca
n see that the measured a
n
d sim
u
lated results are
alm
o
st the sa
m
e
. It shows that the re
turn loss
increases at lower fre
que
nc
y
and
decrea
ses
at
hi
ghe
r f
r
eq
u
e
ncy
.
Thi
s
i
s
beca
us
e of
t
h
e
sol
d
e
r
i
n
g a
nd
fee
d
t
h
at
d
o
es
not
t
ouc
h
wel
l
at
t
h
e
gr
ou
n
d
pl
ane, a
d
di
t
i
onal
l
y
t
h
i
s
an
tenn
a is m
a
n
u
a
l fab
r
ication were it is d
i
fficu
lt to
ach
iev
e
th
e sam
e
resu
lt as th
e si
m
u
latio
n
.
Th
e sim
u
lated
b
a
ndw
id
th and m
easu
r
ed
b
a
nd
w
i
d
t
h
o
f
th
e
an
tenn
a is almo
st th
e sam
e
fo
r
l
o
w
e
r
f
r
e
quen
c
y b
a
nd
an
d lo
ok
s
sm
al
l
e
r bi
t
for
t
h
e hi
ghe
r f
r
e
que
ncy
ba
nd
.
The m
easured val
u
e
of t
h
e
ban
d
wi
dt
h i
s
60 k
H
z (
1
.
7
5
GHz
–
1.
82
5
GHz
)
fo
r
l
o
we
r f
r
e
que
nc
y
ban
d
a
n
d
13
M
H
z (
2
.
4
5G
H
z
–
2.
3
2
G
H
z
)
f
o
r
hi
ghe
r
fre
qu
ency
ba
n
d
.
(a)
(b
)
Fig
u
re
5
.
(a) Si
m
u
la
tio
n
an
d
Measu
r
em
en
t resu
lt, (b)
An
ten
n
a
und
er m
e
a
s
u
r
em
en
t test
3.
2. Be
ndin
g
Ante
nn
a E
x
pe
riment
for
Str
u
ctur
al He
alth Moni
torin
g
Sys
t
em
Fi
gu
re
6 sh
o
w
s t
h
e m
i
crost
r
i
p
pat
c
h ant
e
nn
a un
de
rg
o f
o
r
st
rai
n
m
easurem
ent
at
di
ffer
e
nt
t
y
pe o
f
bending. It
is s
h
ows
the
fa
bri
cated
a
n
tenna
connected to t
h
e FSMA and
n
e
two
r
k
an
alyser
.
Figu
r
e
6(
a)
sh
ow
s
the
ante
nna
is at
0 degree where no
ben
d
i
n
g
he
nce t
h
e f
r
eq
ue
ncy
i
s
n
o
t
chan
gi
n
g
.
A
f
t
e
r t
h
at
w
e
be
nd
t
h
e
ant
e
n
n
a t
o
10
deg
r
ee as s
h
o
w
n i
n
Fi
g
u
re
6(
b)
, t
h
e
n
we
cont
i
n
ue i
n
c
r
e
a
si
ng t
h
e a
n
gl
e up t
o
5
5
de
gree
a
s
sh
own
Figu
re
6
(
e). Figure 2
illu
strates a ty
p
i
cal b
u
ild
i
n
g
wh
ich
was app
lied
to
strain, in
creasing
th
e fo
rce
appl
i
e
d t
o
b
u
i
l
di
ng i
n
crease
s
t
h
e be
ndi
ng
angl
e
of t
h
e
bui
l
d
i
n
g
.
As a
t
0 de
gree
be
ndi
ng
, i
t
i
s
m
ean t
h
e
m
i
crost
r
i
p
pat
c
h i
s
no
rm
al
and t
h
e
r
e i
s
n
o
fo
rce bei
ng
appl
i
e
d t
o
t
h
e
ant
e
nna as s
h
o
w
n i
n
Fi
g
u
r
e
6(a)
.
Ap
pl
y
i
ng
s
o
m
e
f
o
rce t
o
t
h
e
b
u
i
l
d
i
n
g ca
uses
t
o
be
n
d
t
h
e an
ten
n
a
with th
e
co
rresp
ond
ing angle.
If we
i
n
crease
th
e fo
rce it will cau
se m
o
re b
e
n
d
i
n
g
and
i
n
creases th
e ang
l
e of th
e an
ten
n
a
.
Fi
gu
re
7 s
h
o
w
s t
h
e
ben
d
i
n
g
r
e
sul
t
s
f
r
om
VNA
, as
we ca
n see from
the graph
whe
n
e
v
er we inc
r
ease
th
e ang
l
e or
deg
r
ee t
h
en th
e
freq
u
e
n
c
y
will sh
ift to
righ
t
also
. So
in
t
h
is co
nd
ition
we
can
say th
at
ben
d
i
n
g
and a
n
gl
e i
s
d
i
rect
l
y
pro
p
o
r
t
i
onal
t
o
eac
h
ot
he
r. At
t
h
e
begi
nni
ng t
h
e
fre
que
ncy
wa
s
app
r
o
x
i
m
at
ely
fro
m
1.
8G
Hz t
o
2.
4
GHz w
h
i
c
h i
s
sho
w
n bl
ack c
o
l
o
ur
, and st
rai
n
was n
o
t
appl
i
e
d t
o
t
h
e ant
e
nna s
o
t
h
e ant
e
nna i
s
i
n
t
h
e
n
o
r
m
a
l
no
b
e
n
d
i
n
g.
S
econ
d
t
h
e
pat
c
h
was
be
nt
20
deg
r
ee a
n
d t
h
e
fr
eq
ue
ncy
s
h
i
f
t
s
f
r
om
(
1
.
8
G
H
z
-
2
.
4
G
Hz) t
o
(1
.8
75-2.49
GHz), as we in
crease th
e force th
e
an
g
l
e
o
f
in
ci
d
e
n
t
will also
b
e
larg
er. In
add
itio
n
a
4
0
d
e
g
r
ee
b
e
n
d
sh
ifts th
e
freq
u
e
n
c
y to
2
.
08
-2
,65
G
Hz.
An
d
lastly 55
d
e
g
r
ee
o
f
b
e
nd
will cau
se th
e larg
est
sh
ifting
o
f
th
is
an
tenn
a.
Th
is data is su
mm
ari
zed
in Tab
l
e 3.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
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502
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52
I
ndo
n
e
sian
J Elec Eng
& Com
p
Sci, V
o
l. 10
,
No
.
3
,
Jun
e
2
018
:
91
7 – 92
4
92
2
Tabl
e
3.
A
n
t
e
n
n
a a
ngl
e
be
ndi
ng
vs
f
r
e
que
nc
y
shi
f
t
.
Antenna angle bending (
d
egr
ee)
Fr
equency
shifting
in GHz
0
1.
8 -
2.
4
10
1.
875
-
2
.
4
9
20
1.
9-
2.
59.
40
2.
08-
2.
65.
55
2.
108-
2.
78.
(a
)
0
degr
ee
(
b
)
20
de
gre
e
(
c
)
30 de
gree
(
d
)
35
de
gre
e
(
e
)
40
degree
(f
)
55 de
gree
Figure
6. E-Shape a
n
tenna
under di
f
f
ere
n
t
b
e
ndi
ng
m
easurem
ent
t
e
st
Fig
u
r
e
7
.
Bend
i
ng resul
t
fr
om
0
de
gr
ee t
o
5
5
degr
ee
4.
CO
NCL
USI
O
N
Th
e m
a
in
o
b
j
ectiv
e o
f
th
is
research
was t
o
in
v
e
stig
ate th
e feasib
ility o
f
m
easu
r
ing
strain
u
s
i
n
g
m
i
crost
r
i
p
pat
c
h a
n
t
e
n
n
as.
W
h
i
c
h i
s
c
o
m
p
act
and
ha
ve
hi
g
h
gain
an
tenn
a th
at is su
itab
l
e for stru
ctural
h
ealth
m
oni
t
o
ri
ng a
p
pl
i
cat
i
on. T
h
e rel
a
t
i
ons
hi
p
bet
w
ee
n t
h
e
shi
f
t
o
f
t
h
e re
son
a
nt
f
r
eq
ue
ncy
of a
rect
ang
u
l
a
r
micro
s
trip
p
a
tch
an
tenn
a an
d
th
e strain
app
lied
to
th
e
ant
e
n
n
a i
s
di
scusse
d
for
fi
ve di
ffe
r
ent
ben
d
i
n
g a
n
gl
es.
Evaluation Warning : The document was created with Spire.PDF for Python.
In
d
onesi
a
n
J
E
l
ec En
g &
C
o
m
p
Sci
ISS
N
:
2
5
0
2
-
47
52
St
ruct
ural
He
a
l
t
h
Mo
ni
t
o
ri
n
g
Sen
s
or
b
a
se
d o
n
a
Fl
exi
bl
e Mi
crost
r
i
p
…
(
H
a
m
se
A
b
di
l
l
ahi
Haj
i
Omer)
92
3
The res
u
lts indicate that the resonant
f
r
eq
ue
ncy
of t
h
e a
n
t
e
nna s
h
i
f
t
s
by
a
ppl
y
i
n
g
st
rai
n
t
h
at
sh
ows i
n
cr
easi
n
g
the be
ndi
ng a
ngle inc
r
eases
the fre
quency
shift. Strain
measurem
ent
using
slotted rectangular
m
i
c
r
ost
r
i
p
p
a
tch
an
tenn
a p
r
op
o
s
ed
in
th
i
s
d
e
sign
is an
oth
e
r area of d
e
v
e
lop
m
en
t wh
ich
will h
a
v
e
i
m
p
o
r
tan
t
ad
v
a
n
t
ag
es
ove
r cu
rre
nt st
rain se
nso
r
s.
Hence i
n
the
fut
u
re this
des
i
gn c
oul
d be
devel
ope
d
by
addi
ng c
r
o
ss s
l
ot
s t
o
measure
the di
rection of
the strain
al
so and h
o
w m
u
ch
strain
is app
lied
t
o
th
e
rectangu
lar p
a
tch
an
tenn
a, t
o
b
eco
m
e
m
o
re
i
n
teresting
.
ACKNOWLE
DGE
M
ENTS
Th
e au
tho
r
s
g
r
atefu
lly ackn
o
wledg
e
u
s
e o
f
th
e
services an
d
facilities o
f
th
e Adv
a
n
c
ed
C
o
m
m
uni
cat
i
o
n E
ngi
neeri
n
g
C
e
nt
re (
A
C
E
) C
o
E
,
Sc
ho
ol
of C
o
m
put
er
and
C
o
m
m
uni
cat
i
on En
gi
n
e
eri
n
g,
Un
i
v
ersiti Malaysia Perlis (Un
i
MAP).
Th
is
p
r
oj
ect also
b
e
en
fun
d
e
d
b
y
Fu
nd
am
en
tal Research Gran
t Sch
e
m
e
(
F
RGS)
90
03-0
054
5.
REFERE
NC
ES
[1]
Z. Yinhai
, e
t
al
.
,
"
A
No
vel S
VPW
M Modulation S
c
heme,
"
in Applied Power Electr
onics Conferen
ce and Exposition
,
2009. APEC 200
9. Twen
ty
-Fourth Annual I
E
EE,
2009, pp
. 128-1
31.
[2]
Daliri,
Ali,
et al.
"
C
ircu
lar microstrip patch a
n
tenna strain sensor
for wireless structural hea
lth monitorin
g
.
"
Proceedings of
t
h
e W
o
rld Congr
ess on Engin
eer
i
ng, vol
. 2
,
2010
.
[3]
Widodo,
Achmad, et al.
"Dev
elopment of
Wireless Smart Sensor for
Structure
and Mach
ine Monitoring
."
TELKOMNIKA (Telecommunica
tion Computing
Electronics and
Control)
, 2013;
11 (2): 417-
424.
[4]
Sur
y
anita, R
e
ni.
"Intelligent Br
id
ge Seism
i
c Mon
itoring
S
y
stem
Based on N
e
uro
Genetic H
y
br
id."
TE
LKOMNIK
A
(
T
elecommunication Computing
Electronics and
Control)
,
2017;
15 (4): 1830~18
40.
[5]
Putra, Seno
Adi,
et
al
. "Conc
eptua
l
Design
of Multi-
agent
S
y
stem
for Sur
a
m
a
du Bridge
Structura
l
Hea
l
t
h
Monitoring S
y
stem."
TELKOM
NIKA (
T
elecommunication Co
m
puting Electro
n
ics and Control)
,
2015; 13 (3):
1079-1088.
[6]
R. Matsuzak
i,
M. Meln
y
kow
y
c
z, and
A. Todor
oki, “Ant
enna/sensor m
u
ltifunct
i
onal
co
m
posites for the wireles
s
detection
of d
a
mage,”
Compos. S
c
i. Techno
l
., vol. 69, no. 15–16, p
p
. 2507–2513
, 2
009.
[7]
Downe
y
, Aus
tin
, et
al
. "Dam
age
dete
ction
,
lo
ca
li
zat
ion and qu
ant
i
fic
a
tion
in cond
uctiv
e s
m
art con
c
ret
e
s
t
ruc
t
ure
s
using a r
e
sistor
mesh model."
Engineering
Structures,
no
.148, pp
. 924-935
, 2017
.
[8]
U.
Tata,
H.
Huang,
R.
L.
Carter,
and J. C. Chiao
,
“Exploiting a p
a
tch
antenn
a for
s
t
rain m
eas
urem
ents
,”
M
e
as. Sci.
Technol
., vo
l. 20
, no
. 1
,
pp
. 1520
1, 2009
.
[9]
R. Di S
a
nt
e,
“
F
ibre Opti
c S
e
ns
ors
for S
t
ructur
al He
a
lth
Monitoring of Air
c
raf
t
Co
mposite Str
u
ctures: Recent
Advances and
A
pplications,”
Se
nso
rs (B
a
s
e
l
)
, vol. 15
, no
. 8
,
pp
. 1
8666–713, 2015
.
[10]
W. Clem and
L.
Zhang, “Fact
behind Build
ing C
o
llapse in Shang
h
ai,” pp
. 16
, 200
9.
BIOGRAP
HI
ES OF
AUTH
ORS
Ham
s
e abdillah
i
haji was born
in Hargeisa, So
m
a
lia,
in 1994. He received
th
e Bach
elor of
Engineering (Ho
nours) (Commu
nication Eng
i
neeri
ng) degr
ee
fr
om University
Malay
s
ia Per
lis,
Mala
y
s
ia
in 201
7. During his stu
d
ies, h
e
is a
t
op student
in class, cons
equently
up
on graduation
he being
awarded the Vice-Chan
cellor Gold Me
d
a
l Award at the
12th Convocatio
n Ceremon
y
of
UniM
AP
.
His
current inter
e
s
t
are
m
i
cros
trip
pa
tch
antenn
a and
m
i
c
r
owave
r
e
s
ear
ch area
.
Dr. Saidatul Norl
y
a
na Azem
i
obtain
e
d her Ph.D in 2014 fro
m
Roy
a
l Melbo
u
rne Institute
Techno
log
y
(R
MIT) University, Melbourne Au
stra
lia. She has
received th
e Masters of Science
in Communication Engineer
ing in 2010 from Un
iversi
ty
Malay
s
ia Perlis, Ma
lay
s
ia. Previous
ly
,
she obtained her first degree f
r
om University
Malay
s
ia Perlis, Malay
s
ia, with Honors, in
Communication Engineering, graduating in 2007. In
RMIT
University
Melbourn
e
Australia, Dr.
S
a
idatul was
a winner for P
o
s
t
er and Oral pres
entation two
y
ear
in a row during
Higher Degree
b
y
Research Co
nference’s day
RMIT as well as
School of Electrical and Computer Engin
eering
(S
ECE) P
o
s
t
graduate Res
e
arch
Da
y. Dr. S
a
idat
ul was
the recip
i
ent of the Bes
t
S
t
udent P
a
per
Award pres
ent
e
d at
the
M
a
l
a
ys
ian T
echni
ca
l
Universiti
es Co
nference on
En
gineer
ing and
Techno
log
y
(M
UCET 2017). She has published seve
ral impact factor journ
a
ls
, nation
a
l and
intern
ation
a
l co
nferenc
e
pap
e
rs
.
S
h
ee is
current
l
y
a S
e
n
i
or Le
ct
urer at th
e S
c
ho
ol of Com
puter
and Com
m
unica
tion Eng
i
ne
ering
(SCCE), Univ
e
r
s
iti Mal
a
y
s
ia
Perlis (UniMAP).
Her rese
arch
inter
e
s
t
focus
on
3-D and 2D F
r
equenc
y S
e
l
ect
ive
S
u
rface,
3-D an
tenna s
t
ru
cture
,
antenn
a des
i
gn
and div
e
rsity
,
dielectric ma
terials, wireless netw
ork,
and
RF
&
m
i
crowave
des
i
gn
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
502
-47
52
I
ndo
n
e
sian
J Elec Eng
& Com
p
Sci, V
o
l. 10
,
No
.
3
,
Jun
e
2
018
:
91
7 – 92
4
92
4
Ping Jack Soh, C.Eng, was bor
n in Sabah, Malay
s
ia. He rece
i
v
ed the Bac
h
el
or and M
a
s
t
er
degrees in E
l
ec
tric
al Engin
eer
i
ng (Tele
c
om
m
u
nica
tion) from
Universiti T
e
kn
ologi Mala
ysi
a
(UTM) in 2002
and 2006, respectiv
ely
,
and th
e
Ph
D degree in Electrical Engin
e
ering from KU
Leuven
,
Belgiu
m in 2013. He
is curren
t
ly
an Asso
ciate Professor at
the Schoo
l o
f
Computer and
Communication Engineering (SCCE),
Univers
i
t
i
M
a
la
y
s
ia P
e
rl
is
(UniM
A
P
)
. He res
earch
es
and
publis
hes
activ
el
y in his
areas
of
interes
t: we
arab
le ant
e
nnas
,
arr
a
ys
, m
e
tas
u
rfa
ces
and s
y
s
t
em
s
;
on-bod
y
communication; electrom
agnetic saf
e
ty
and absorpti
on; and wireless and radar
techn
i
ques
for heal
thcar
e appl
i
cat
ions
. Dr. S
oh was
the recip
i
ent of th
e IEE
E
Antennas
and
Propagation Society
(AP-S) Doctoral R
e
search
Award in 2012
, th
e IEEE Microwave Th
eor
y
an
d
Techn
i
ques Society
(MTT-S) Graduate Fellowshi
p for Medical Applications in 2013 and the
International Union of Radio Science (URSI) Y
oung Scientist A
w
ard in 2015. He was also the
Second Place Winner of
the I
E
E
E
Presidents
'
Ch
ange th
e World
Com
p
etition
and
IEEE
MTT-S
Video Competition, both
in 2
013. He is a
Charter
e
d Engineer reg
i
ster
ed
with the UK
Engineering Cou
n
cil; a Senior M
e
mber of th
e I
E
EE, a Member o
f
the IET, ACES
and URSI;
and
a Graduat
e
M
e
m
b
er of the BE
M
and the IEM
.
He als
o
s
e
rves
in the IE
EE M
T
T-S
EduCom
m,
and th
e I
EEE
M
TT-S M&S Com
m
ittee
.
Azremi Abdullah Al-Hadi was born on August 26, in
Mich
igan
, United States o
f
America. He
received
the Master of
Science degr
ee
in
co
mmunication engineer
ing fro
m Birmingham
University
, United Kingdom in 2004 and the Doctor of Scien
c
e in Technolog
y
degr
ee from
Aalto University, Finland in 2013. His current re
search interests include design an
d performance
evalu
a
tion of m
u
lti-e
l
em
ent
ant
e
nnas, m
obile t
e
rm
in
al antenn
as and their user in
tera
ctions,
and
wireless propag
a
tion
.
He is curr
entl
y working
a
s
an Associate
Professor and holds position as
Dean of the School of Com
puter and Com
m
uni
cat
ion Engineeri
ng, Universiti
Malay
s
ia Perl
is
(UniMAP). He has been
with
th
e school since 2
002. He is activ
e in
volunteer
work with I
E
EE
Mala
y
s
ia Se
ctio
n, ac
ting as th
e
Senior Mem
b
er of IEEE
, ex
ec
utive
com
m
ittee
in the IE
EE
Antenna Propagation / Micro
w
ave Theor
y
t
echn
i
ques / E
l
ec
trom
agneti
c
Com
p
atibili
t
y
(AP/MTT/EMC) Malay
s
ia Chap
ter and Counselo
r
for the IEEE UniMAP Student Branch. He is
the Chart
e
red E
ngineer of the I
n
stitution of En
gineer
ing and T
echnolog
y
(IE
T)
, UK and the
m
e
m
b
er of the
Board of
Engine
ers
M
a
la
ys
i
a
(B
EM
), M
a
l
a
y
s
ia
.
Dr. Azrem
i
was
the r
ecip
i
ent
of
the B
e
st Studen
t
Paper
Award
presented
at
th
e 5th
Loughboro
ugh Antennas
and Propagation
Conference (
L
APC 2009) and
th
e CST Univ
ersity
Publication
Award in 201
1.
Mohd Faizal Jamlos is an As
so
ciate Professor in Advanced
Co
mmunication En
gineer
ing Centr
e
(ACE), School
of Com
puter an
d Com
m
unicatio
n E
ngineering
at
the Univ
ersiti
Malay
s
ia Per
lis,
Malay
s
ia. He o
b
tain
ed his Ph.D in 2010 from
Universiti T
e
k
nologi Malay
s
i
a
, Malay
s
i
a
and
M.Eng. degr
ee in Electrical and
Electronic from
University
of Adelaide, Australia in 2008. His
first degree is
from
Universiti Malay
s
i
a
Pe
rlis, Mal
a
y
s
ia, with Honours, in Com
puter
Engineering in 2
006. He has auth
ored over 200
p
ublications,
including 80 peer-r
eviewed journ
a
l
papers, 129 conf
erence pap
e
rs, 3
book chapters an
d fi
ve patents. H
e
has serv
ed as a reviewer for
Trans
a
c
tion M
i
c
r
owave Theor
y
& Techn
i
que
, T
r
ansaction Antenna & Propagation, Progress in
Ele
c
trom
agnet
i
c
s
Res
earch
, IE
T
M
i
crowaves
an
d TP
C for few
intern
ation
a
l
co
nferenc
e
s
.
His
current
res
ear
ch
inter
e
s
t
s
inc
l
ud
e Advanc
ed M
i
crowaves
M
e
t
a
m
a
teria
l
s
,
M
i
cro
w
ave Im
aging,
On-platform
El
ectrom
a
gne
tism
of autom
o
tiv
e and V2X Co
mmunication s
y
stem and Io
T
applications. He has been r
eco
gnized in providing training
and consultations
on Test and
M
eas
urem
ent s
y
s
t
em
s
and M
i
cr
owave & RF
T
r
ans
ceiv
e
r Des
i
gn to various
c
o
m
p
anies
and
univers
iti
es
. He
is
a S
e
nior Mem
b
er of IEEE,
M
a
la
y
s
i
a
M
e
di
cal Res
e
arch
er (NM
RR), and
Professional En
gineer
of Bo
ard
of
Engineers
Ma
lay
s
ia. He also appointed as Academ
y
Tr
ainer
of MikroTik and certif
ied for
Network Asso
ci
ate,
Traff
i
c C
ontrol Engin
eer
and Routing
Engineer.
Evaluation Warning : The document was created with Spire.PDF for Python.