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1.
I
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RO
D
UCT
I
O
N
T
h
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p
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s
s
o
f
f
i
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t
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k
n
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w
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as
p
o
s
itio
n
i
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g
[
1
]
.
T
h
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t
w
o
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p
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p
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s
itio
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in
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p
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th
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n
m
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n
t
in
w
h
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s
p
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f
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.
I
n
o
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td
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GP
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is
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t
h
e
m
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t
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m
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f
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.
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k
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n
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m
ai
n
l
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d
u
e
to
t
h
r
ee
r
ea
s
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n
s
[
2
]
.
Fo
r
GP
S
to
w
o
r
k
w
ell,
it
n
ee
d
s
L
in
e
Of
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t
(
L
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w
it
h
i
n
t
h
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GP
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s
at
ellites
a
n
d
t
h
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r
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s
.
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e
s
ec
o
n
d
r
ea
s
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is
t
h
e
b
u
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in
g
m
ater
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s
.
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t
ca
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p
ass
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t
h
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m
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ter
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g
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m
ater
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lik
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r
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f
s
,
w
alls
etc.
T
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ir
d
r
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is
th
at
GP
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s
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n
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co
m
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n
d
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ca
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g
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(
Ultr
a
Hi
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q
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)
s
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ca
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ter
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t
h
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ak
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S si
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s
to
n
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r
k
p
r
o
p
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r
ly
.
T
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e
tech
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o
lo
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s
u
s
ed
f
o
r
in
d
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r
p
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itio
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ar
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R
FID
[
3
]
,
B
lu
eto
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th
[
4
]
,
W
i
-
Fi
[
5
]
,
Ultr
aso
u
n
d
[
6
]
,
VL
C
[
7
]
etc.
Se
v
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al
c
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ar
ac
te
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is
tics
ar
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s
ed
f
o
r
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ati
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r
P
o
s
itio
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S
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s
te
m
(
I
P
S)
[
1
]
.
T
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ar
e
ac
cu
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,
p
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,
u
p
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c
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co
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p
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co
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o
f
f
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co
m
p
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tin
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,
lo
ca
lis
atio
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ti
m
e
an
d
i
n
f
r
astr
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ctu
r
e.
I
P
S
h
a
s
s
e
v
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al
ap
p
lic
atio
n
s
i
n
o
u
r
r
ea
l
li
f
e
[
1
,
8
]
.
T
h
ey
h
e
lp
in
th
e
n
av
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g
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n
o
f
v
is
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all
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b
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lik
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all
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m
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m
s
.
Na
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lace
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t
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I
P
Ss
.
An
o
th
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m
p
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tan
t
ap
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f
I
P
S
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at
th
e
y
p
r
o
v
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m
ed
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ca
r
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in
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o
s
p
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T
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h
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in
tr
ac
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in
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p
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tien
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th
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eq
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in
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Fire
f
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p
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s
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
9
,
No
.
5
,
Octo
b
er
2
0
1
9
:
3
9
2
7
-
3933
3928
I
n
d
o
o
r
p
o
s
itio
n
in
g
tec
h
n
o
lo
g
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ca
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b
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cla
s
s
i
f
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s
e
v
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w
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s
[
1
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.
T
h
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y
ca
n
b
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c
lass
if
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n
t
h
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b
asis
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f
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.
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tech
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tech
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d
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ased
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ased
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n
in
f
r
astr
u
ct
u
r
e
p
o
s
itio
n
in
g
ar
c
h
itect
u
r
e
t
h
e
lo
ca
tio
n
o
f
th
e
o
b
j
ec
t
is
o
b
tain
e
d
w
it
h
i
n
t
h
e
co
v
er
a
g
e
ar
ea
.
O
b
j
ec
ts
ca
lcu
late
t
h
e
p
o
s
itio
n
b
y
t
h
e
m
s
el
v
es
i
n
s
elf
p
o
s
it
io
n
i
n
g
ar
c
h
i
tect
u
r
e.
Ho
w
e
v
er
,
s
el
f
-
o
r
ie
n
ted
in
f
r
astru
ct
u
r
e
–
ass
is
ted
ar
ch
itect
u
r
e
m
ai
n
l
y
d
ep
en
d
s
o
n
th
e
s
y
s
te
m
th
at
e
s
ti
m
ates
th
e
p
o
s
itio
n
.
B
ased
o
n
th
e
m
ed
i
u
m
u
s
ed
f
o
r
p
o
s
itio
n
in
g
cla
s
s
i
f
icat
io
n
ca
n
b
e
d
o
n
e
in
to
u
ltra
s
o
u
n
d
,
m
ag
n
etic,
r
ad
io
f
r
eq
u
e
n
c
y
,
v
i
s
io
n
-
b
ased
an
d
a
u
d
ib
le
s
o
u
n
d
tec
h
n
o
lo
g
ies.
I
n
d
o
o
r
p
o
s
itio
n
i
n
g
tech
n
o
lo
g
ie
s
ca
n
c
lass
i
f
ied
i
n
to
i
n
d
o
o
r
p
ed
estri
an
p
o
s
itio
n
in
g
a
n
d
f
i
x
ed
in
d
o
o
r
p
o
s
itio
n
i
n
g
s
y
s
t
e
m
.
Dep
en
d
i
n
g
o
n
th
e
a
v
aila
b
le
p
r
io
r
k
n
o
w
led
g
e
I
P
S
ca
n
b
e
class
i
f
ied
i
n
to
p
ar
am
etr
ic
a
n
d
n
o
n
p
ar
a
m
etr
ic
tech
n
o
lo
g
ies.C
lass
if
ica
tio
n
is
also
d
o
n
e
b
ased
o
n
th
e
ty
p
e
o
f
s
e
n
s
o
r
lik
e
ca
m
er
a,
R
FID
,
W
L
AN
an
d
W
i
-
Fi,
i
n
f
r
ar
ed
etc.
I
n
co
n
tr
ast
to
th
e
ab
o
v
e
cl
ass
i
f
icatio
n
s
,
in
d
o
o
r
p
o
s
itio
n
in
g
tec
h
n
o
lo
g
ies
ca
n
b
e
ca
teg
o
r
ized
d
ep
en
d
in
g
o
n
t
h
e
in
f
r
astr
u
ctu
r
e
u
s
ed
b
y
t
h
e
s
y
s
te
m
[
1
]
.
T
h
e
y
ca
n
b
e
class
i
f
ied
in
to
b
u
il
d
in
g
d
ep
en
d
en
t
a
n
d
b
u
ild
in
g
in
d
ep
en
d
e
n
t.
B
u
ild
i
n
g
d
ep
en
d
en
t
in
d
o
o
r
p
o
s
itio
n
in
g
tec
h
n
o
lo
g
ies
ca
n
b
e
class
i
f
ied
b
ased
o
n
tech
n
o
lo
g
ies
th
a
t
u
s
e
b
u
il
d
in
g
's
i
n
f
r
astru
ct
u
r
e
a
n
d
t
ec
h
n
o
lo
g
ies
th
a
t
u
s
e
d
ed
ic
ated
in
f
r
astr
u
ctu
r
e.
Wi
-
Fi,
B
lu
e
to
o
th
an
d
C
ell
u
l
ar
b
ased
ar
e
th
e
tech
n
o
lo
g
i
es
th
at
u
s
e
b
u
ild
i
n
g
'
s
i
n
f
r
as
tr
u
ctu
r
e.
Ded
icate
d
in
f
r
astru
ct
u
r
e
i
s
u
s
ed
b
y
tec
h
n
o
lo
g
ies
li
k
e
R
FID
,
Z
i
g
b
ee
,
Ultr
aso
n
ic
a
n
d
I
n
f
r
ar
ed
.
B
u
ild
in
g
i
n
d
ep
en
d
en
t
in
d
o
o
r
p
o
s
itio
n
in
g
tec
h
n
o
lo
g
ies
ca
n
b
e
cla
s
s
i
f
ied
i
n
to
D
ea
d
R
ec
k
o
n
i
n
g
an
d
I
m
ag
e
-
b
ased
tech
n
o
lo
g
ies.
Dea
d
r
ec
k
o
n
in
g
lo
ca
tes
cu
r
r
en
t
p
o
s
itio
n
b
ased
o
n
th
e
p
ast
s
p
ee
d
,
d
ir
ec
tio
n
an
d
p
o
s
itio
n
.
I
m
ag
e
-
b
ase
d
tech
n
o
lo
g
ies
d
ep
en
d
o
n
ca
m
er
as
an
d
o
th
er
v
i
s
io
n
-
b
ased
t
ec
h
n
o
lo
g
ies.
I
m
a
g
ed
-
b
a
s
ed
tech
n
o
lo
g
ies
ca
n
b
e
eith
e
r
b
u
ild
i
n
g
d
ep
en
d
en
t
o
r
b
u
ild
in
g
in
d
ep
en
d
e
n
t.
I
m
a
g
e
-
b
ased
tech
n
o
lo
g
ie
s
th
a
t
ar
e
b
u
ild
in
g
d
ep
en
d
en
t
m
ai
n
l
y
r
el
y
o
n
a
m
ap
o
f
t
h
e
b
u
ild
in
g
o
r
s
p
ec
ial
s
ig
n
s
o
f
th
e
b
u
ild
in
g
s
.
Ho
w
ev
er
,
i
m
ag
e
-
b
ased
tech
n
o
lo
g
ie
s
th
at
ar
e
b
u
ild
i
n
g
i
n
d
ep
en
d
en
t
d
o
n
o
t d
ep
en
d
o
n
an
y
s
i
g
n
s
o
r
m
ap
o
f
th
e
b
u
ild
in
g
.
Mo
b
ile
R
o
b
o
t
I
n
d
o
o
r
Po
s
itio
n
in
g
S
y
s
te
m
h
a
s
lar
g
e
n
u
m
b
er
o
f
ap
p
licatio
n
s
i
n
o
u
r
d
a
y
to
d
a
y
li
f
e
li
k
e
tr
an
s
p
o
r
tatio
n
,
ass
i
s
ta
n
ce
d
u
r
i
n
g
t
h
e
ti
m
e
o
f
s
u
r
g
er
ies
etc.
A
p
ar
t
f
r
o
m
t
h
is
,
t
h
e
y
h
elp
in
v
ar
io
u
s
m
i
litar
y
ac
tiv
itie
s
lik
e
s
co
u
ti
n
g
a
n
d
an
ti
-
ter
r
o
r
is
m
.
Ho
w
e
v
er
,
ex
is
ti
n
g
in
d
o
o
r
p
o
s
itio
n
in
g
s
y
s
te
m
u
s
in
g
m
o
b
ile
r
o
b
o
ts
f
ac
e
t
h
e
p
r
o
b
lem
o
f
p
o
o
r
p
o
s
itio
n
in
g
ac
c
u
r
ac
y
.
T
h
er
ef
o
r
e
i
n
o
r
d
er
to
o
v
er
co
m
e
t
h
i
s
,
T
ay
l
o
r
Ser
ies
Me
th
o
d
i
n
T
im
e
D
if
f
er
en
ce
o
f
A
r
r
i
v
al
a
p
p
r
o
ac
h
u
s
i
n
g
f
iv
e
s
e
n
s
o
r
c
o
o
r
d
in
ates
is
u
s
ed
i
n
t
h
is
p
ap
er
w
h
ic
h
p
r
o
v
id
es
a
m
o
r
e
ac
c
u
r
ate
r
esu
l
t.
2.
R
E
L
AT
E
D
WO
RK
Dif
f
er
en
t
m
ea
s
u
r
e
m
e
n
t
ap
p
r
o
ac
h
es
ar
e
u
s
ed
in
I
n
d
o
o
r
P
o
s
itio
n
i
n
g
S
y
s
te
m
[
9
]
.
T
h
ey
ar
e
R
ec
eiv
e
d
Sig
n
al
Stre
n
g
th
I
n
d
icato
r
(
R
S
SI)
,
T
im
e
o
f
A
r
r
iv
al
(
T
OA
)
,
T
im
e
Di
f
f
er
en
ce
o
f
A
r
r
iv
a
l
(
T
DO
A
)
an
d
An
g
le
o
f
A
r
r
i
v
al
(
A
O
A
)
.
I
n
R
SS
I
,
w
h
e
n
t
h
e
s
ig
n
al
s
tr
a
v
el
f
r
o
m
tr
an
s
m
itter
to
th
e
r
ec
eiv
er
,
t
h
e
y
g
et
atten
u
ated
.
Gr
ea
ter
is
th
e
ch
a
n
ce
o
f
atte
n
u
atio
n
as
th
e
d
is
tan
ce
g
ets
lo
n
g
er
.
T
h
er
ef
o
r
e
th
e
d
is
tan
ce
w
it
h
i
n
th
e
tr
an
s
m
itter
an
d
t
h
e
r
ec
e
iv
er
is
ca
lc
u
lated
b
y
u
s
i
n
g
th
e
s
tr
en
g
t
h
o
f
s
ig
n
al
r
ec
ei
v
ed
.
Dis
ta
n
ce
ca
n
b
e
esti
m
ate
d
f
r
o
m
in
f
o
r
m
at
io
n
lik
e
tr
a
n
s
m
it
ted
s
i
g
n
al
p
o
w
er
,
r
ec
eiv
ed
s
i
g
n
al
s
tr
en
g
t
h
,
p
ath
lo
s
s
m
o
d
el
etc.
T
OA
i
s
t
h
e
m
o
s
t
co
m
m
o
n
l
y
u
s
ed
tech
n
iq
u
e.
I
n
t
h
is
m
et
h
o
d
th
e
ex
ac
t
ti
m
e
at
w
h
ich
t
h
e
s
i
g
n
al
s
ar
e
s
en
t
f
r
o
m
t
h
e
tr
an
s
m
i
tter
s
an
d
th
e
e
x
ac
t
ti
m
e
at
w
h
ic
h
th
e
s
i
g
n
als
r
ea
ch
t
h
e
r
ec
eiv
er
is
r
eq
u
ir
ed
.
T
DOA
is
th
e
s
ec
o
n
d
m
o
s
t
co
m
m
o
n
l
y
u
s
ed
tech
n
iq
u
e.
T
h
is
is
t
h
e
ti
m
e
d
i
f
f
er
en
ce
t
h
e
s
ig
n
al
tak
e
s
to
ar
r
iv
e
f
r
o
m
t
r
an
s
m
itter
s
to
r
ec
eiv
er
s
.
Her
e
it
r
eq
u
ir
es
o
n
l
y
th
e
ti
m
e
at
w
h
ich
t
h
e
s
i
g
n
al
ar
r
i
v
es
th
e
r
ec
ei
v
er
.
C
o
m
p
ar
ed
to
T
OA
th
e
p
o
s
s
ib
ilit
y
o
f
o
cc
u
r
r
en
ce
o
f
er
r
o
r
is
le
s
s
an
d
ac
cu
r
ac
y
o
f
th
e
r
es
u
lt
o
b
t
ain
ed
is
m
o
r
e
.
A
O
A
is
t
h
e
d
ir
ec
tio
n
o
f
ar
r
iv
al
o
f
s
i
g
n
als
at
t
h
e
r
ec
eiv
er
f
r
o
m
t
h
e
tr
an
s
m
i
tter
s
.
T
h
e
d
ir
ec
tio
n
ca
n
b
e
o
b
tain
ed
b
y
m
ea
s
u
r
in
g
th
e
an
g
le
b
et
w
ee
n
th
e
tr
a
n
s
m
i
tter
s
an
d
r
ec
eiv
er
s
.
T
h
e
m
et
h
o
d
is
n
o
t
th
at
w
id
el
y
u
s
ed
s
in
ce
t
h
is
r
eq
u
ir
es
th
e
in
s
tallat
io
n
s
p
ec
ial
an
te
n
n
as.
B
ased
o
n
th
e
g
eo
m
etr
y
o
f
t
h
e
tr
a
n
s
m
itter
n
o
d
es
an
d
r
ec
eiv
er
n
o
d
e
s
,
t
h
e
p
o
s
itio
n
i
n
g
ac
c
u
r
ac
y
ca
n
b
e
in
cr
ea
s
ed
[
1
0
]
.
I
n
o
r
d
er
to
h
av
e
b
etter
ac
cu
r
ac
y
,
P
o
s
itio
n
Dil
u
tio
n
o
f
P
r
ec
is
io
n
(
P
DOP
)
v
alu
e
s
h
o
u
ld
b
e
less
.
P
DOP
is
th
e
er
r
o
r
in
p
o
s
itio
n
d
u
e
to
t
h
e
g
eo
m
e
tr
y
.
I
t c
a
n
b
e
w
r
itte
n
as t
h
e
s
q
u
ar
e
r
o
o
t o
f
HDOP
s
q
u
ar
e
p
lu
s
VD
O
P
s
q
u
ar
e.
HDOP
is
t
h
e
Ho
r
izo
n
tal
Dil
u
t
io
n
o
f
P
r
ec
is
io
n
an
d
V
DOP
is
th
e
Ver
tica
l
Dil
u
tio
n
o
f
P
r
ec
i
s
io
n
.
HD
OP
is
t
h
e
s
q
u
ar
e
r
o
o
t
L
aDO
P
(
L
atit
u
d
e
Dilu
tio
n
o
f
P
r
ec
is
io
n
)
s
q
u
ar
e
p
l
u
s
L
o
DOP
(
L
o
n
g
itu
d
e
Dil
u
tio
n
o
f
P
r
ec
is
io
n
)
s
q
u
ar
e.
Ultr
aso
n
ic
s
en
s
o
r
s
ar
e
w
id
el
y
u
s
ed
f
o
r
p
o
s
itio
n
in
g
b
ec
au
s
e
o
f
its
lo
w
co
s
t
a
n
d
b
etter
ac
cu
r
ac
y
i
t
p
r
o
v
id
es.
Ultr
aso
n
ic
I
n
d
o
o
r
P
o
s
itio
n
i
n
g
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.
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m
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b
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r
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b
o
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in
s
id
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b
u
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in
g
s
[
1
2
]
.
T
h
is
s
y
s
te
m
u
s
e
s
T
DOA
m
et
h
o
d
f
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s
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itter
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h
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ti
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eter
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T
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ic
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s
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tter
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s
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th
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te
m
w
h
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s
e
co
o
r
d
in
ates
ar
e
k
n
o
w
n
a
n
d
f
ix
ed
.
T
E
L
I
A
M
ADE
is
a
L
P
S
u
s
in
g
w
ir
eles
s
u
ltra
s
o
n
ic
s
e
n
s
o
r
s
[
1
3
]
.
T
h
is
s
y
s
te
m
p
r
o
v
id
es
ce
n
ti
m
e
ter
lev
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ac
cu
r
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y
.
I
n
t
h
i
s
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y
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te
m
th
e
p
o
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n
s
u
m
p
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s
s
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d
h
a
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a
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etter
n
et
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co
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r
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eq
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lo
w
m
e
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t.
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F
m
o
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le
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et
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ic
p
o
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n
i
n
g
s
y
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te
m
is
u
s
ed
in
[
1
4
]
,
w
h
er
e
w
ea
r
ab
le
an
d
m
o
b
ile
co
m
p
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te
r
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ar
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s
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to
ca
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late
th
e
p
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O
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th
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ili
n
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f
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ic
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n
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r
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k
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t
an
d
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to
a
c
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tr
o
ller
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d
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r
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ce
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ic
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als
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ea
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late
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th
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n
a
n
ac
cu
r
ac
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r
an
g
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o
f
1
0
c
m
an
d
2
5
c
m
.
Sch
ed
u
l
in
g
o
f
m
o
b
ile
r
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b
o
t
c
an
b
e
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o
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s
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n
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i
n
d
o
o
r
p
o
s
itio
n
in
g
s
y
s
te
m
[
1
5
]
.
Ho
w
e
v
er
,
u
ltra
s
o
n
ic
s
en
s
o
r
s
ar
e
n
o
t
s
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it
a
b
le
f
o
r
lar
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e
ar
ea
s
.
T
o
o
v
er
co
m
e
t
h
is
,
m
u
l
ti
-
b
lo
ck
ap
p
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o
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h
is
u
s
ed
w
h
ich
is
d
o
n
e
b
y
d
iv
id
i
n
g
t
h
e
lar
g
e
ar
ea
s
in
to
s
ev
er
al
b
lo
ck
s
w
ith
m
u
ltip
le
s
e
n
s
o
r
s
in
ea
c
h
b
lo
ck
.
B
ea
co
n
s
ch
ed
u
li
n
g
alg
o
r
ith
m
i
s
u
s
ed
f
o
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esti
m
ati
n
g
t
h
e
lo
ca
tio
n
o
f
t
h
e
m
o
b
ile
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o
b
o
ts
.
C
er
tain
ad
v
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ta
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e
s
o
f
u
s
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n
g
t
h
i
s
m
e
th
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ar
e
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at
th
e
o
b
s
tacle
p
r
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b
lem
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ce
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to
an
ex
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t,
lar
g
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ea
s
ca
n
b
e
c
o
n
s
id
er
ed
f
o
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p
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itio
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g
,
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etter
p
lace
m
en
t
o
f
s
en
s
o
r
s
is
p
o
s
s
ib
le,
an
d
m
o
r
e
m
o
b
ile
r
o
b
o
ts
ca
n
b
e
d
etec
ted
.
C
er
tain
d
r
a
w
b
ac
k
s
i
n
cl
u
d
e
d
if
f
ic
u
lt
y
i
n
r
ec
o
g
n
iz
in
g
th
e
b
o
u
n
d
ar
y
b
et
w
ee
n
ea
c
h
b
lo
ck
s
a
n
d
co
llis
io
n
p
r
o
b
le
m
.
Nav
ig
a
tio
n
o
f
m
o
b
ile
r
o
b
o
t
ca
n
b
e
d
o
n
e
b
y
u
s
in
g
la
s
er
r
an
g
e
f
i
n
d
er
,
n
at
u
r
al
lan
d
m
ar
k
s
an
d
co
m
p
a
s
s
[
1
6
]
.
C
o
r
n
er
s
i
n
th
e
r
o
o
m
ar
e
co
n
s
id
er
ed
as
n
atu
r
al
la
n
d
m
ar
k
s
h
er
e.
Af
ter
d
etec
tin
g
t
h
e
co
r
n
er
s
,
th
e
p
o
s
itio
n
o
f
th
e
co
r
n
e
r
s
ar
e
esti
m
ated
b
y
u
s
i
n
g
t
h
e
r
o
b
o
t's
m
o
v
i
n
g
d
ir
ec
tio
n
w
h
ic
h
i
s
i
n
d
icate
d
b
y
th
e
co
m
p
a
s
s
.
C
er
tai
n
as
s
u
m
p
tio
n
s
ar
e
m
ad
e
h
er
e.
i.e
.
th
e
r
o
b
o
ts
ca
n
s
ee
th
e
la
n
d
m
ar
k
s
at
all
ti
m
e
a
n
d
n
o
o
b
j
ec
ts
ar
e
s
i
m
i
lar
to
th
e
lan
d
m
ar
k
s
i
n
t
h
e
en
v
ir
o
n
m
e
n
t.
L
o
ca
tio
n
B
ased
P
o
s
itio
n
in
g
s
y
s
te
m
u
s
i
n
g
R
F
a
n
d
u
ltr
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o
n
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s
i
g
n
als
b
ased
o
n
T
DO
A
g
i
v
e
er
r
o
r
s
[
1
7
]
.
T
h
is
is
d
u
e
to
th
e
lack
o
f
L
i
n
e
O
f
Si
g
h
t
(
L
O
S)
o
f
t
h
e
u
ltra
s
o
n
ic
s
ig
n
al
s
.
T
h
er
ef
o
r
e
to
in
cr
ea
s
e
t
h
e
ac
cu
r
ac
y
an
d
to
i
m
p
r
o
v
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th
e
p
er
f
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r
m
a
n
ce
a
n
o
v
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l
T
DOA
b
ased
p
o
s
itio
n
esti
m
ati
n
g
tec
h
n
iq
u
e
is
u
s
ed
w
h
ic
h
u
s
e
u
ltra
s
o
n
ic
r
e
f
lectio
n
s
i
n
lo
ca
tio
n
e
s
t
i
m
a
tio
n
.
T
h
is
g
i
v
es
a
h
i
g
h
p
o
s
itio
n
i
n
g
ac
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r
ac
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n
d
er
r
o
r
less
th
a
n
3
5
c
m
e
v
en
w
h
en
t
h
e
L
i
n
e
O
f
Sig
h
t o
f
s
ig
n
als
f
r
o
m
t
h
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u
ltra
s
o
n
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s
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s
o
r
s
i
s
b
lo
ck
ed
.
A
ct
iv
e
B
at
s
y
s
te
m
u
s
ed
f
o
r
ca
lcu
lati
n
g
th
e
o
r
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tat
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n
an
d
p
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s
itio
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o
f
o
b
j
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ts
in
s
id
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th
e
b
u
ild
in
g
s
c
o
n
s
is
t
o
f
r
ec
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k
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o
w
n
p
o
s
i
tio
n
an
d
t
h
e
y
ar
e
co
n
n
ec
ted
to
a
P
C
[
1
8
]
.
R
F
r
ec
eiv
er
a
n
d
u
ltra
s
o
n
ic
tr
a
n
s
m
itter
s
ar
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p
lace
d
o
n
ea
c
h
r
o
v
er
.
An
R
F
m
es
s
ag
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s
e
n
t
b
y
th
e
P
C
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2
0
0
m
s
.
T
h
is
R
F
m
e
s
s
a
g
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co
n
tai
n
s
t
h
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i
n
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o
r
m
atio
n
ab
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t
t
h
e
r
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v
er
t
h
at
i
s
go
in
g
to
s
en
d
th
e
u
ltra
s
o
n
ic
s
ig
n
al
s
.
T
h
e
r
ec
eiv
er
r
ec
eiv
es
th
ese
u
ltra
s
o
n
ic
s
ig
n
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an
d
w
ith
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h
e
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elp
o
f
m
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ltil
ater
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n
,
t
h
e
p
o
s
itio
n
o
f
t
h
e
r
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v
er
is
ca
lc
u
lated
.
I
n
C
R
I
C
KE
T
s
y
s
te
m
,
t
h
e
tr
an
s
m
it
ter
s
t
h
at
ar
e
k
ep
t
o
n
th
e
ce
ili
n
g
o
f
t
h
e
b
u
ild
in
g
e
m
i
t
R
F
an
d
t
h
e
u
l
tr
aso
n
ic
s
i
g
n
als
[
1
9
]
.
R
F
is
p
lace
d
o
n
th
e
m
o
b
ile
p
latf
o
r
m
w
h
ic
h
is
m
ai
n
l
y
u
s
ed
f
o
r
t
h
e
s
y
n
c
h
r
o
n
is
at
io
n
o
f
t
h
e
tr
a
n
s
m
itte
r
s
an
d
t
h
e
r
ec
ei
v
er
.
T
OA
m
et
h
o
d
is
u
s
ed
f
o
r
ca
lcu
lati
n
g
th
e
p
o
s
itio
n
o
f
t
h
e
m
o
b
ile
u
n
it.
T
h
e
r
ec
eiv
er
is
p
l
ac
ed
o
n
th
e
m
o
b
ile
u
n
it
.
T
h
is
s
y
s
te
m
p
r
o
v
id
es
a
n
ac
cu
r
ac
y
o
f
ap
p
r
o
x
i
m
atel
y
2
0
cm
.
DO
L
P
HI
N
s
y
s
te
m
i
s
d
ev
elo
p
ed
to
r
e
d
u
ce
th
e
co
n
f
i
g
u
r
atio
n
co
s
t
o
f
all
s
en
s
o
r
n
o
d
es
[
2
0
]
.
T
h
ey
p
r
o
v
id
e
p
h
y
s
ica
l
lo
ca
tio
n
tr
ac
k
in
g
in
lar
g
e
ar
ea
s
w
it
h
b
etter
ac
cu
r
ac
y
co
m
p
ar
ed
to
o
th
er
s
y
s
te
m
s
li
k
e
A
ct
i
v
e
B
at
an
d
C
r
ick
e
t.
T
h
is
s
y
s
te
m
s
e
n
d
s
an
d
r
ec
eiv
e
s
u
l
tr
aso
n
ic
a
n
d
R
F
s
i
g
n
als
f
r
o
m
t
h
e
d
is
tr
ib
u
ted
w
ir
eles
s
s
e
n
s
o
r
n
o
d
es.
T
o
d
if
f
er
en
t
i
n
d
o
o
r
o
b
j
ec
ts
,
th
e
s
e
s
e
n
s
o
r
n
o
d
es
ar
e
atta
ch
ed
.
T
h
is
s
y
s
te
m
p
r
o
v
id
es
p
o
s
itio
n
i
n
g
w
i
th
les
s
m
a
n
u
al
co
n
f
i
g
u
r
atio
n
w
it
h
t
h
e
h
elp
o
f
a
d
is
tr
ib
u
ted
p
o
s
itio
n
in
g
alg
o
r
it
h
m
a
n
d
w
it
h
a
n
ac
cu
r
ac
y
o
f
ar
o
u
n
d
1
5
c
m
.
Ho
w
e
v
er
in
[
1
4
,
1
8
,
1
9
]
a
n
ar
r
o
w
b
a
n
d
,
th
e
u
ltra
s
o
n
ic
s
e
n
s
o
r
s
u
s
ed
h
av
e
ce
r
tai
n
li
m
i
tat
i
o
n
s
[
2
1
]
.
T
h
e
f
ir
s
t
li
m
itatio
n
is
t
h
at
t
h
e
s
ig
n
als
ca
n
i
n
ter
f
er
e
w
it
h
o
n
e
an
o
t
h
er
if
m
o
r
e
th
a
n
co
llo
ca
ted
s
en
s
o
r
s
e
m
it
s
ig
n
al
s
at
t
h
e
s
a
m
e
ti
m
e.
T
h
e
s
ec
o
n
d
li
m
itatio
n
is
th
at
s
lo
w
d
ata
r
ates o
f
n
ar
r
o
w
b
a
n
d
s
y
s
te
m
s
m
a
k
e
i
t d
if
f
ic
u
lt
to
en
co
d
e
a
u
n
iq
u
e
id
e
n
ti
f
ier
in
t
h
e
s
h
o
r
t
-
ti
m
e
r
an
g
i
n
g
s
i
g
n
al
s
.
T
h
u
s
it
b
ec
o
m
e
s
d
if
f
ic
u
lt
to
s
ep
ar
ate
t
h
e
s
ig
n
al
s
f
r
o
m
d
i
f
f
er
en
t ta
g
s
f
o
r
a
r
ec
eiv
er
.
I
n
th
e
p
r
esen
ce
o
f
n
o
is
e,
th
e
s
y
s
te
m
s
h
o
w
s
p
o
o
r
p
er
f
o
r
m
a
n
ce
,
w
h
ich
is
th
e
th
ir
d
li
m
ita
tio
n
.
T
o
o
v
er
co
m
e
th
e
s
e
p
r
o
b
le
m
s
,
b
r
o
ad
b
a
n
d
u
ltra
s
o
n
i
c
tr
a
n
s
m
itter
s
an
d
r
ec
eiv
er
s
ar
e
u
s
ed
.
T
h
is
s
y
s
te
m
p
r
o
v
id
es c
er
tai
n
a
d
v
an
ta
g
es.
T
h
e
f
ir
s
t a
d
v
an
ta
g
e
is
n
o
is
e
r
o
b
u
s
t
n
es
s
.
T
h
at
i
s
,
t
h
e
s
y
s
te
m
p
r
o
v
id
e
s
th
e
lo
ca
tio
n
u
p
d
ates
e
v
en
i
n
n
o
i
s
e.
T
h
e
s
ec
o
n
d
ad
v
a
n
t
ag
e
is
t
h
at
i
t
p
r
o
v
id
es
i
n
cr
ea
s
ed
u
p
d
ate
r
ates.
B
r
o
ad
b
an
d
u
ltra
s
o
n
ic
s
y
s
te
m
s
p
r
o
v
id
e
lo
w
-
late
n
c
y
p
o
s
iti
o
n
in
g
w
h
ic
h
is
th
e
t
h
ir
d
ad
v
an
ta
g
e.
T
h
e
y
also
p
r
o
v
id
e
en
h
an
ce
d
id
en
tific
atio
n
en
co
d
in
g
w
h
ich
i
s
t
h
e
f
o
u
r
t
h
ad
v
an
ta
g
e.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
9
,
No
.
5
,
Octo
b
er
2
0
1
9
:
3
9
2
7
-
3933
3930
3.
P
RO
P
O
SE
D
WO
RK
Af
ter
g
o
in
g
th
r
o
u
g
h
m
a
n
y
lit
er
atu
r
e
r
ev
ie
w
s
,
p
ap
er
[
2
2
]
u
s
ed
u
ltra
s
o
n
ic
i
n
d
o
o
r
p
o
s
itio
n
i
n
g
s
y
s
te
m
ca
lled
I
C
KON.
T
h
e
I
C
KON
s
y
s
te
m
es
ti
m
ates
t
h
e
lo
ca
tio
n
o
f
t
h
e
m
o
b
ile
u
n
i
t
at
ce
n
ti
m
e
tr
e
-
le
v
el
ac
cu
r
ac
y
b
y
u
s
i
n
g
u
l
tr
aso
n
ic
s
i
g
n
al
s
.
Her
e
th
e
f
o
u
r
u
ltra
s
o
n
ic
s
en
s
o
r
s
ar
e
p
lace
d
at
k
n
o
w
n
p
o
s
itio
n
s
an
d
th
e
y
s
en
d
s
ig
n
al
s
p
er
io
d
ically
.
T
i
m
e
Dif
f
er
e
n
ce
o
f
A
r
r
i
v
al
(
T
DOA
)
o
f
s
i
g
n
al
s
is
u
s
ed
b
y
t
h
e
r
ec
eiv
er
w
h
i
ch
is
p
lace
d
o
n
th
e
m
o
b
ile
u
n
it
to
es
ti
m
ate
t
h
e
lo
ca
tio
n
o
f
t
h
e
m
o
b
ile
u
n
it.
L
ea
s
t
Sq
u
ar
e
(
L
S)
m
et
h
o
d
is
u
s
e
d
to
s
o
lv
e
th
e
s
et
o
f
eq
u
atio
n
s
d
u
e
to
it
s
lo
w
co
m
p
lex
it
y
.
E
q
u
atio
n
s
f
o
r
m
ed
b
y
u
s
i
n
g
T
DOA
o
f
s
i
g
n
als
ca
n
b
e
s
o
lv
ed
b
y
u
s
i
n
g
d
if
f
er
e
n
t
m
et
h
o
d
s
to
o
b
tain
t
h
e
p
o
s
itio
n
o
f
th
e
m
o
b
ile
u
n
i
t
b
ased
o
n
t
h
e
co
m
p
lex
it
y
a
n
d
r
estrictio
n
s
[
2
3
]
.
T
h
ey
ar
e
An
al
y
tical
Me
t
h
o
d
(
A
M)
,
L
ea
s
t
Sq
u
ar
e
Me
th
o
d
(
L
S),
T
ay
lo
r
Ser
ies
Me
th
o
d
(
T
S),
A
p
p
r
o
x
im
a
te
Max
i
m
u
m
L
i
k
eli
h
o
o
d
m
et
h
o
d
(
A
M
L
)
,
T
w
o
-
S
tag
e
Ma
x
i
m
u
m
L
ik
el
ih
o
o
d
m
et
h
o
d
(
T
SML
)
a
n
d
Ge
n
etic
A
l
g
o
r
ith
m
(
G
A
)
.
T
ay
lo
r
Ser
i
es
m
et
h
o
d
g
i
v
es
les
s
er
r
o
r
a
s
co
m
p
ar
ed
to
o
t
h
er
m
et
h
o
d
s
.
T
h
e
y
ar
e
u
s
ed
to
lin
ea
r
ize
t
h
e
n
o
n
-
li
n
ea
r
eq
u
ati
o
n
s
[
2
4
]
.
T
h
ey
i
g
n
o
r
e
t
h
e
m
e
asu
r
e
m
en
t
e
r
r
o
r
s
an
d
p
r
o
v
id
e
an
ac
c
u
r
ate
r
es
u
lt
ev
en
at
n
o
is
e
lev
el
s
co
m
p
ar
ed
to
th
e
L
ea
s
t
Sq
u
ar
e
m
et
h
o
d
.
T
h
er
ef
o
r
e
in
th
is
p
ap
er
,
T
ay
lo
r
Ser
ies
(
T
S)
m
et
h
o
d
is
u
s
ed
as t
h
i
s
g
i
v
es a
m
o
r
e
ac
c
u
r
ate
r
esu
l
t th
a
n
L
ea
s
t Sq
u
ar
e
(
L
S)
m
eth
o
d
.
T
h
e
p
r
o
p
o
s
ed
s
o
lu
tio
n
d
o
n
e
i
n
t
h
is
p
ap
er
to
p
r
o
v
id
e
a
m
o
r
e
ac
cu
r
ate
r
esu
lt
i
n
i
n
d
o
o
r
p
o
s
itio
n
i
n
g
s
y
s
te
m
u
s
in
g
m
o
b
ile
r
o
b
o
t
is
to
u
s
e
T
ay
lo
r
Ser
ies
m
eth
o
d
i
n
T
DOA
ap
p
r
o
ac
h
u
s
i
n
g
f
i
v
e
s
en
s
o
r
co
o
r
d
in
ates.
So
f
ar
r
esear
ch
er
s
h
a
v
e
u
s
ed
T
ay
lo
r
Ser
ies
m
et
h
o
d
in
T
DOA
ap
p
r
o
ac
h
u
s
i
n
g
f
o
u
r
u
l
tr
aso
n
ic
s
e
n
s
o
r
s
.
As
t
h
e
n
u
m
b
er
o
f
tr
a
n
s
m
it
ter
s
i
n
cr
ea
s
es
t
h
e
ac
c
u
r
ac
y
o
f
t
h
e
s
y
s
te
m
al
s
o
in
cr
ea
s
e
s
[
2
3
]
.
T
h
e
d
if
f
er
en
ce
b
et
w
ee
n
t
h
e
ac
tu
al
lo
ca
tio
n
a
n
d
th
e
est
i
m
a
t
ed
lo
ca
tio
n
is
r
ed
u
ce
d
to
p
r
o
v
i
d
e
a
m
o
r
e
ac
cu
r
ate
r
es
u
lt.
3
.
1
.
Alg
o
rit
h
m
1.
Sig
n
als ar
e
r
ec
eiv
ed
f
r
o
m
t
h
e
5
u
ltra
s
o
n
ic
s
ig
n
als.
2.
T
h
e
R
ec
eiv
er
p
lace
d
o
n
th
e
m
o
b
ile
u
n
it
u
s
es T
DO
A
ap
p
r
o
ac
h
to
ca
lcu
late
t
h
e
p
o
s
itio
n
.
3.
T
o
esti
m
ate
t
h
e
p
o
s
itio
n
o
f
t
h
e
m
o
b
ile
u
n
it T
ay
lo
r
Ser
ies M
e
th
o
d
is
u
s
ed
[
2
3
]
.
4.
W
e
d
ef
in
e
a
f
u
n
c
tio
n
w
it
h
T
DOA
e
s
ti
m
atio
n
w
i
th
(
i+1
)
th
r
e
f
er
en
ce
n
o
d
e
an
d
r
an
g
e
est
i
m
a
tio
n
er
r
o
r
.
(
)
√
(
)
(
)
√
(
)
(
)
(
1
)
w
h
er
e
(
x
,
y
)
i
s
th
e
lo
ca
tio
n
co
o
r
d
in
ate
o
f
th
e
m
o
b
ile
u
n
it a
n
d
(
x
i+
1,
y
i
+
1
)
is
t
h
e
(
i+1
)
th
r
ef
er
e
n
ce
n
o
d
e.
5.
T
h
e
I
n
itial
e
s
ti
m
at
io
n
o
f
t
h
e
m
o
b
ile
u
n
i
t
i
s
ta
k
e
n
.
A
ct
u
al
lo
ca
tio
n
ca
n
b
e
w
r
itte
n
as
th
e
s
u
m
o
f
in
itia
l
lo
ca
tio
n
an
d
lo
ca
tio
n
esti
m
at
io
n
er
r
o
r
s
w
h
ic
h
w
e
h
av
e
to
f
in
d
o
u
t.
(x
v,
y
v
)
is
t
h
e
in
itia
l
esti
m
at
io
n
o
f
th
e
m
o
b
ile
u
n
i
t.
δ
x
an
d
y
ar
e
th
e
lo
ca
tio
n
esti
m
atio
n
er
r
o
r
s
.
6.
T
h
en
th
e
f
u
n
ctio
n
d
e
f
i
n
ed
in
s
tep
5
is
ex
p
an
d
ed
in
to
T
ay
lo
r
Ser
ies.
(
2
)
w
h
er
e
(
)
an
d
an
d
ar
e
th
e
p
ar
tial
d
er
iv
ativ
es
o
f
t
h
e
f
u
n
ctio
n
d
ef
in
ed
in
s
tep
5
w
it
h
r
esp
ec
t to
x
an
d
y
7.
E
q
u
atio
n
(
2
)
ca
n
b
e
w
r
itte
n
as
A
δ=
D+
E
(
3
)
A=
[
]
,
δ=
,
-
, E=
,
-
,
D=
,
-
8.
W
eig
h
t
L
ea
s
t Sq
u
ar
e
esti
m
at
i
o
n
is
u
s
ed
to
s
o
lv
e
th
is
a
n
d
h
el
p
s
to
f
in
d
lo
ca
tio
n
es
ti
m
atio
n
er
r
o
r
.
(
)
(
4
)
w
h
er
e
Q=
*
+
,
is
a
co
v
ar
ian
ce
m
at
r
ix
w
it
h
ze
r
o
-
m
ea
n
Ga
u
s
s
ian
r
an
d
o
m
v
ar
iab
les a
s
ele
m
en
t
s
.
9.
L
o
ca
tio
n
es
ti
m
atio
n
i
s
co
n
ti
n
u
o
u
s
l
y
u
p
d
ated
w
i
th
t
h
e
lo
ca
tio
n
esti
m
atio
n
er
r
o
r
.
10.
B
y
iter
ati
n
g
th
e
ab
o
v
e
p
r
o
ce
d
u
r
es,
th
e
lo
ca
tio
n
esti
m
atio
n
ca
n
b
e
co
n
tin
u
o
u
s
l
y
r
e
f
i
n
e
d.
Evaluation Warning : The document was created with Spire.PDF for Python.
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th
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o
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n
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n
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a
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ated
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[
2
5
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2
6
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.
R
MSE
o
b
tain
ed
in
T
ab
le1
f
o
r
T
ay
lo
r
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ies
Me
th
o
d
is
2
.
1
1
m
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s
t
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ar
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th
o
d
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3
8
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2
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n
d
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tical
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t
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7
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h
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r
l
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s
h
o
w
s
th
at
T
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Me
th
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d
p
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v
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s
er
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al
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h
at
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ay
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Ser
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et
h
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m
et
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d
in
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ap
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s
ed
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it
h
f
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s
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ates.
Sin
ce
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h
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ates.
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ab
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2
s
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w
s
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h
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r
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f
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Me
t
h
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s
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ates.
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r
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s
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ates.RM
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u
s
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n
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n
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s
s
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ate
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ic
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e
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er
r
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tain
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h
e
n
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o
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te
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ed
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Fig
u
r
e
1
s
h
o
w
s
t
h
e
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m
p
ar
i
s
o
n
o
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er
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r
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u
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g
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e
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r
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ates
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d
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e
n
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ates.
I
t
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r
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d
ep
icts
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at
er
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r
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ates a
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ates.
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e
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lt o
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t Sq
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h
e
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lt o
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l
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ic
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ay
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n
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ates
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[1
]
S
.
A
l
-
h
a
d
h
ra
m
i,
e
t
a
l.
,
“
Ultra
W
id
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a
n
d
In
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o
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o
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h
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ies
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.
1
-
3
6
,
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0
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.
[2
]
F
.
Dw
i
y
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sa
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M
.
L
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m
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A
S
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o
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g
,
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p
p
.
4
-
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Oc
t
2
0
1
6
.
[3
]
C.
Hu
a
n
g
,
e
t
a
l.
,
“
Re
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l
-
T
i
m
e
RF
ID
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o
o
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o
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6
4
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p
p
.
7
2
8
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3
9
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0
1
5
.
[4
]
P
.
Kriz
,
e
t
a
l.
,
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L
o
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y
Be
a
c
o
n
s,” v
o
l.
2
0
1
6
,
2
0
1
6
.
[5
]
U
.
Of
,
“
W
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.
1
5
0
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7
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M
a
r
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0
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.
[6
]
A
.
Ya
z
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c
i,
e
t
a
l.
,
“
A
n
Ultras
o
n
ic
Ba
se
d
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o
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m
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p
p
.
5
8
5
-
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8
9
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0
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1
.
[7
]
M
.
S
.
Ra
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m
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n
d
K.
Ki
m
,
“
I
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Im
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e
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so
rs,”
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l.
1
,
p
p
.
1
6
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1
.
[8
]
Y
.
G
u
,
e
t
a
l.
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n
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l
Ne
tw
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rk
s,” v
o
l.
1
1
,
p
p
.
1
3
-
3
2
,
2
0
0
9
.
[9
]
M
.
F
a
ro
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-
i
-
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z
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m
,
“
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o
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ti
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S
e
n
so
r
Ne
tw
o
rk
s,” p
p
.
1
-
5
2
.
[1
0
]
J.
L
i,
e
t
a
l.
,
“
A
n
In
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o
o
r
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tras
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tern
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h
in
g
s,” v
o
l.
2
0
1
6
,
2
0
1
6
.
[1
1
]
J.
Qi
a
n
d
G
.
L
iu
,
“
A
Ro
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st Hi
g
h
-
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c
c
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ra
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n
d
In
d
o
o
r,
”
2
0
1
7
.
[1
2
]
A
.
Ya
z
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c
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a
l.
,
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A
n
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se
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m
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”
p
p
.
5
8
5
-
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8
9
,
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0
1
1
.
[1
3
]
S
.
Ne
tw
o
rk
,
“
A
Ro
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c
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ra
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n
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2
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.
[1
4
]
C.
Ra
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siti
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ste
m
⋆
,
”
2
0
1
4
.
[1
5
]
R.
S
.
Na
ir,
“
S
c
h
e
d
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li
n
g
o
f
In
d
o
o
r
M
o
b
il
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Ro
b
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si
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g
Ultras
o
n
ic
,
”
v
o
l
.
1
,
p
p
.
8
-
1
2
,
2
0
1
4
.
[1
6
]
O.
P
a
rlak
tu
n
a
,
e
t
a
l.
,
“
L
o
c
a
li
z
a
ti
o
n
o
f
a
M
o
b
il
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R
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b
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si
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g
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tu
ra
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L
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rk
s
a
n
d
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si
o
n
,
”
v
o
l
.
2
6
4
8
0
,
p
p
.
3
-
6.
[1
7
]
K.
Kim
,
e
t
a
l.
,
“
Ultras
o
n
i
c
Re
f
lec
ti
o
n
s,”
p
p
.
1
-
1
4
,
2
0
1
6
.
[1
8
]
A
.
Ward
,
e
t
a
l.
,
“
A
Ne
w
L
o
c
a
ti
o
n
T
e
c
h
n
iq
u
e
f
o
r
th
e
A
c
ti
v
e
Off
i
c
e
.
”
[1
9
]
S
.
M
.
C.
S
c
ien
c
e
,
e
t
a
l
.
,
“
T
h
e
Crick
e
t
In
d
o
o
r
L
o
c
a
ti
o
n
S
y
ste
m
,
”
2005.
[2
0
]
Y.
F
u
k
u
j
u
,
e
t
a
l.
,
“
Do
l
p
h
in
:
A
n
a
u
to
n
o
m
o
u
s
in
d
o
o
r
p
o
siti
o
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i
n
g
sy
ste
m
in
u
b
iq
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it
o
u
s
c
o
m
p
u
ti
n
g
e
n
v
iro
n
m
e
n
t,
”
in
Pro
c
.
o
f
t
h
e
IEE
E
W
o
rk
sh
o
p
o
n
S
o
ft
w
a
re
T
e
c
h
n
o
lo
g
ies
fo
r
Fu
t
u
re
Emb
e
d
d
e
d
S
y
ste
ms
.
W
a
sh
in
g
t
o
n
,
DC,
US
A:
IEE
E
Co
m
p
u
ter
S
o
c
iety
,
p
p
.
5
3
-
57
,
2
0
0
3
.
[2
1
]
S
.
M
.
C.
S
c
ien
c
e
,
e
t
a
l
.
,
“
T
h
e
Crick
e
t
In
d
o
o
r
L
o
c
a
ti
o
n
S
y
ste
m
,
”
2005.
[2
2
]
U.
Ya
y
a
n
,
e
t
a
l.
,
“
A
L
o
w
Co
st
U
lt
ra
so
n
ic
Ba
se
d
P
o
siti
o
n
in
g
S
y
ste
m
f
o
r
th
e
In
d
o
o
r
Na
v
ig
a
ti
o
n
o
f
M
o
b
i
le
Ro
b
o
ts,
”
p
p
.
5
4
1
-
5
5
2
,
2
0
1
5
.
[2
3
]
G
.
S
h
e
n
,
e
t
a
l.
,
“
P
e
r
f
o
rm
a
n
c
e
C
o
m
p
a
riso
n
o
f
T
O
A
a
n
d
T
D
O
A
Ba
se
d
L
o
c
a
ti
o
n
Esti
m
a
ti
o
n
A
lg
o
rit
h
m
s
in
L
OS
En
v
iro
n
m
e
n
t,
”
v
o
l.
2
0
0
8
,
2
0
0
8
.
[2
4
]
X
.
L
i
,
e
t
a
l.
,
“
Co
n
tr
ib
u
ted
Re
v
iew
:
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o
u
rc
e
-
lo
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a
li
z
a
ti
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n
a
lg
o
rit
h
m
s
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n
d
a
p
p
li
c
a
ti
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s
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sin
g
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im
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d
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re
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l
m
e
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e
n
ts
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tri
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ted
Re
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w
:
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o
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-
lo
c
a
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m
s
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n
ts,
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v
o
l.
4
1
5
0
2
,
2
0
1
6
.
[2
5
]
Y.
R.
Ha
m
d
y
a
n
d
S
.
A
.
M
a
w
jo
u
d
,
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o
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A
ss
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s,
”
p
p
.
9
9
-
1
0
4
,
2
0
1
2
.
[2
6
]
E.
J.
Nn
e
n
n
a
a
n
d
O.
H.
O
n
y
e
k
a
c
h
i,
“
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o
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il
e
P
o
siti
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n
in
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T
e
c
h
n
iq
u
e
s
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