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h
a
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l
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ise
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ti
o
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d
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o
m
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e
ffe
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ti
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e
ss
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a
d
d
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th
e
se
c
h
a
ll
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g
e
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a
p
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e
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b
a
se
d
o
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th
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e
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e
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ro
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ts,
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e
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ifi
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ll
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e
ra
ti
o
n
s.
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term
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in
g
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in
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s
c
h
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ra
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teriz
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g
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ter
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k
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a
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sis
o
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d
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p
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th
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p
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ly
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s
TL
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d
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s
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ti
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c
t
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m
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n
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e
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o
n
v
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n
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o
n
e
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d
e
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p
so
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n
d
c
h
a
n
n
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l
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n
d
re
li
a
b
le
a
c
o
u
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a
th
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in
th
e
d
e
e
p
se
a
.
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is
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ims
to
q
u
a
n
ti
fy
t
h
e
d
e
tec
ti
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a
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f
u
n
d
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ter
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ti
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b
e
a
c
o
n
s
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u
n
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e
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v
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rio
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s
d
e
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p
-
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sc
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n
a
rio
s
a
n
d
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g
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ra
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s.
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a
n
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ly
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i
n
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UL
B
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n
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l
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ro
p
a
g
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ti
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h
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ra
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ss
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lt
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ra
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ey
w
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r
d
s
:
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ir
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n
d
m
u
ltip
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p
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p
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Pas
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n
ar
Sear
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Sig
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-
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Un
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wate
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T
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CC B
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C
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Kaja
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Dep
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Ab
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titu
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Scien
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T
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I
NT
RO
D
UCT
I
O
N
Un
d
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wate
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s
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m
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(
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f
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ap
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f
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itime
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s
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g
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s
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e
n
v
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o
n
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en
tal
m
o
n
ito
r
in
g
,
u
n
d
er
wate
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r
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b
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ti
cs,
an
d
m
ilit
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an
d
s
ea
r
ch
an
d
r
escu
e
(
SAR
)
o
p
e
r
atio
n
s
[
1
]
–
[1
1
]
.
R
eliab
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u
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d
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m
u
n
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n
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c
r
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o
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ec
tiv
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in
UAC
f
o
r
S
AR
ap
p
licatio
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s
[
1
2
]
–
[
1
6
]
.
Dee
p
-
s
ea
SAR
m
is
s
io
n
s
f
o
r
d
o
wn
ed
air
cr
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t
ar
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cr
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b
u
t
f
ac
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c
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Desp
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wate
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ig
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d
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eter
m
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b
ea
c
o
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'
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m
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s
tan
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s
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t
f
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b
ac
k
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r
o
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n
d
n
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is
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is
cr
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f
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ates
[
1
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[
2
4
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.
T
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On
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[
2
5
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x
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n
i
q
u
e
f
o
r
UW
A
C
M,
p
o
ten
tially
ac
h
iev
i
n
g
b
etter
p
er
f
o
r
m
a
n
ce
th
an
tr
ad
itio
n
al
m
eth
o
d
s
.
I
n
[
2
6
]
,
d
e
ep
n
eu
r
al
n
etwo
r
k
s
(
DNN)
an
d
l
o
n
g
s
h
o
r
t
-
ter
m
m
em
o
r
y
(
L
STM
)
n
etwo
r
k
s
a
r
e
u
tili
ze
d
in
UW
AC
M
to
en
h
an
ce
p
e
r
f
o
r
m
an
ce
.
Ho
wev
er
,
a
n
o
tab
le
ch
allen
g
e
in
ap
p
ly
in
g
m
ac
h
in
e
lear
n
i
n
g
an
d
d
ee
p
lear
n
in
g
tech
n
i
q
u
es
to
u
n
d
e
r
wate
r
ac
o
u
s
tic
co
m
m
u
n
icatio
n
s
is
t
h
e
r
is
k
o
f
o
u
td
ated
ch
an
n
el
s
tate
in
f
o
r
m
atio
n
d
u
e
to
s
ig
n
if
ican
t
p
r
o
p
ag
atio
n
d
elay
s
an
d
d
y
n
am
ic
u
n
d
er
wate
r
en
v
ir
o
n
m
e
n
ts
.
T
o
s
im
u
late
r
ea
lis
tic
u
n
d
er
wate
r
ac
o
u
s
tic
c
h
an
n
els,
r
esear
ch
er
s
o
f
ten
r
ely
o
n
s
p
ec
ialized
b
ea
m
-
tr
ac
in
g
s
o
f
tw
ar
e
s
u
ch
as
B
E
L
L
HOP
[
2
7
]
.
R
esear
ch
er
s
h
av
e
p
r
o
p
o
s
ed
m
ath
em
atica
l
m
o
d
el
s
to
ad
d
r
ess
in
ac
cu
r
ac
ies
in
s
o
u
n
d
v
elo
city
esti
m
atio
n
.
T
h
ese
m
o
d
els
p
r
o
v
id
e
a
co
n
v
er
s
io
n
f
r
am
ewo
r
k
b
etwe
en
atm
o
s
p
h
er
ic
p
r
ess
u
r
e
an
d
d
ep
th
,
aid
in
g
in
s
o
u
n
d
s
p
e
ed
d
eter
m
in
atio
n
.
Ad
v
an
ce
d
m
o
d
elin
g
tech
n
i
q
u
es
lik
e
m
o
d
e
th
eo
r
y
,
p
ar
a
b
o
li
c
eq
u
atio
n
s
,
an
d
f
in
ite
elem
e
n
t
m
eth
o
d
s
ar
e
also
em
p
lo
y
ed
to
s
im
u
late
t
h
e
p
r
o
p
ag
atio
n
o
f
s
o
u
n
d
u
n
d
er
wate
r
,
in
co
r
p
o
r
atin
g
f
ac
to
r
s
s
u
ch
a
s
r
an
g
e
d
ep
en
d
en
ce
an
d
th
e
in
f
lu
e
n
ce
o
f
s
u
r
f
ac
e
an
d
b
o
tto
m
co
n
d
itio
n
s
[
2
8
]
.
T
h
ese
m
eth
o
d
s
h
elp
to
b
etter
u
n
d
e
r
s
tan
d
th
e
u
n
d
er
wate
r
ac
o
u
s
tic
ch
an
n
el
an
d
d
esig
n
ef
f
ec
tiv
e
u
n
d
er
wa
ter
co
m
m
u
n
icatio
n
s
y
s
tem
s
f
o
r
SAR
o
p
er
atio
n
s
.
Desp
ite
th
e
ap
p
licatio
n
o
f
th
ese
m
o
d
els
as
UW
AC
M,
a
u
n
iv
er
s
al
UW
A
C
M
th
at
ca
ter
s
to
all
ap
p
licatio
n
s
an
d
d
iv
er
s
e
o
ce
an
en
v
ir
o
n
m
en
ts
r
em
ain
s
u
n
d
e
f
in
ed
.
Ho
wev
er
,
o
n
e
o
f
th
e
ex
is
tin
g
UW
AC
M
f
o
r
SAR
o
p
er
atio
n
m
o
d
el
[
2
4
]
p
r
im
ar
ily
ad
d
r
ess
es d
ir
ec
t p
ath
p
r
o
p
ag
atio
n
,
leav
in
g
a
g
ap
in
u
n
d
er
s
tan
d
in
g
th
e
im
p
ac
ts
o
f
v
ar
io
u
s
m
u
ltip
ath
s
in
d
ee
p
-
o
ce
a
n
en
v
ir
o
n
m
en
ts
.
T
h
u
s
,
f
o
r
SAR
m
is
s
io
n
s
in
th
e
d
ee
p
s
ea
,
th
e
r
e
is
a
n
ee
d
f
o
r
a
m
o
r
e
ac
cu
r
ate
an
d
less
co
m
p
le
x
U
W
AC
M.
Hen
ce
,
to
o
p
tim
ize
s
ea
r
ch
ef
f
o
r
ts
,
th
is
r
esear
ch
f
o
c
u
s
es
o
n
d
e
v
elo
p
in
g
a
m
o
d
el
to
ac
cu
r
ately
d
eter
m
in
e
b
o
th
T
L
an
d
SNR
f
o
r
d
ir
ec
t
an
d
v
ar
io
u
s
m
u
ltip
ath
s
o
f
d
ee
p
-
s
ea
,
u
ltima
tely
im
p
r
o
v
in
g
th
e
s
u
cc
ess
r
ate
o
f
r
escu
e
m
is
s
io
n
s
.
T
h
is
r
esear
ch
wo
r
k
'
s
p
r
im
ar
y
co
n
tr
ib
u
tio
n
s
ar
e:
−
I
n
itially
,
th
e
m
o
d
el
g
ets
v
ar
i
o
u
s
en
v
ir
o
n
m
en
tal
p
a
r
am
eter
s
lik
e
ch
an
n
el
d
ep
t
h
,
tr
an
s
m
it
ter
an
d
r
ec
eiv
e
r
d
is
tan
ce
,
tem
p
er
atu
r
e,
s
alin
ity
,
p
H,
an
d
o
p
er
atin
g
f
r
eq
u
en
cy
as
in
p
u
ts
to
ca
lc
u
late
th
e
ab
s
o
r
p
tio
n
co
ef
f
icien
t.
−
T
h
en
,
f
o
r
v
a
r
io
u
s
r
an
g
es,
th
e
p
r
o
p
o
s
ed
m
o
d
el
ca
lcu
lates T
L
f
o
r
d
ir
ec
t
p
ath
p
r
o
p
ag
atio
n
.
−
Nex
t,
th
e
m
o
d
el
ca
lcu
lates
th
e
T
L
f
o
r
v
ar
io
u
s
m
u
ltip
ath
p
r
o
p
ag
atio
n
m
o
d
es
in
th
e
d
ee
p
s
ea
,
s
u
ch
as
S
R
,
SD,
B
B
,
C
Z
,
DSC
,
an
d
R
AP.
−
T
h
is
m
o
d
el
u
s
es
a
p
ass
iv
e
s
o
n
ar
eq
u
atio
n
to
p
r
o
v
id
e
a
m
o
r
e
ac
cu
r
ate
p
ictu
r
e
o
f
u
n
d
er
wate
r
b
ea
co
n
s
ig
n
al
b
eh
av
io
r
in
th
e
d
ee
p
s
ea
b
y
d
eter
m
in
in
g
SNR
f
o
r
b
o
t
h
d
ir
ec
t
an
d
v
ar
i
o
u
s
m
u
ltip
ath
s
.
Fo
r
SN
R
d
eter
m
in
atio
n
,
th
e
s
o
u
r
ce
lev
e
l
(
SL)
,
n
o
is
e
lev
el
(
NL
)
,
a
n
d
d
ir
ec
tiv
ity
in
d
e
x
(
DI
)
v
alu
es
ca
n
b
e
co
n
s
id
er
ed
f
r
o
m
th
e
ex
is
tin
g
liter
atu
r
e,
w
h
er
ea
s
th
e
p
r
o
p
o
s
ed
m
o
d
el
f
o
c
u
s
es p
r
im
ar
ily
o
n
T
L
an
d
SNR
ca
lcu
latio
n
.
−
T
h
is
p
ap
er
co
m
p
ar
es
th
e
r
esu
lts
with
ex
is
tin
g
m
o
d
els
to
en
s
u
r
e
ac
cu
r
ac
y
.
T
h
is
is
cr
itical
f
o
r
o
p
tim
izin
g
SAR
s
tr
ateg
ies,
th
er
eb
y
en
h
an
cin
g
th
e
s
u
cc
ess
r
ate
o
f
d
ee
p
-
s
ea
r
escu
e
m
is
s
io
n
s
.
T
h
e
r
est
o
f
th
e
p
ap
e
r
is
s
tr
u
ct
u
r
ed
as
f
o
llo
ws:
s
ec
tio
n
2
p
r
e
s
en
ts
th
e
p
r
o
p
o
s
ed
UW
AC
M
s
y
s
tem
f
o
r
d
ee
p
-
s
ea
SAR
o
p
er
atio
n
s
.
Sectio
n
3
d
is
cu
s
s
es th
e
r
esu
lts
o
f
SNR
f
o
r
d
ir
ec
t a
n
d
v
ar
io
u
s
m
u
ltip
ath
s
in
th
e
d
ee
p
s
ea
.
Sectio
n
4
co
n
clu
d
es th
e
p
r
im
ar
y
o
u
tco
m
es a
n
d
p
r
o
v
id
es
th
e
s
co
p
e
f
o
r
f
u
t
u
r
e
wo
r
k
.
2.
P
RO
P
O
SE
D
P
ASS
I
V
E
UW
ACM F
O
R
DE
E
P
S
E
A
SAR
O
P
E
RAT
I
O
N
Fig
u
r
e
1
p
r
esen
ts
an
o
v
e
r
v
iew
o
f
UW
AC
M
f
o
r
d
etec
tin
g
u
n
d
er
wate
r
lo
ca
t
o
r
ac
o
u
s
tic
b
ea
c
o
n
s
u
s
in
g
p
ass
iv
e
s
o
n
ar
eq
u
atio
n
s
.
T
h
e
d
eter
m
in
atio
n
o
f
SNR
is
cr
itic
al
in
d
etec
tin
g
ac
o
u
s
tic
b
ea
co
n
s
f
r
o
m
u
n
d
er
wate
r
lo
ca
tio
n
b
ea
c
o
n
s
(
UL
B
s
)
in
co
m
p
lex
o
ce
an
en
v
ir
o
n
m
e
n
ts
.
T
h
e
m
u
ltip
ath
p
r
o
p
ag
atio
n
an
d
am
b
ien
t
n
o
is
e
af
f
ec
t
th
e
esti
m
atio
n
o
f
SNR
as
s
h
o
wn
in
Fig
u
r
e
1
.
Acc
u
r
ate
SNR
esti
m
atio
n
is
ess
e
n
tial
to
en
s
u
r
e
th
e
ef
f
ec
tiv
en
ess
o
f
th
e
d
etec
tio
n
p
r
o
ce
s
s
in
v
ar
io
u
s
o
ce
an
c
o
n
d
i
tio
n
s
.
Fig
u
r
e
2
p
r
o
v
i
d
es
th
e
f
lo
w
d
iag
r
am
f
o
r
th
e
p
r
o
p
o
s
ed
UW
AC
M
f
o
r
SAR
o
p
er
atio
n
,
u
s
in
g
a
p
ass
iv
e
s
o
n
ar
eq
u
atio
n
to
d
eter
m
in
e
th
e
SNR
o
f
b
o
th
d
ir
ec
t
an
d
v
ar
io
u
s
m
u
ltip
ath
s
in
th
e
d
ee
p
s
ea
.
T
h
is
r
esear
ch
co
n
ce
n
tr
ates
o
n
th
e
d
ee
p
-
s
ea
en
v
ir
o
n
m
en
t
f
o
r
SAR
o
p
er
ati
o
n
s
.
As
a
r
esu
lt,
th
is
p
ap
er
p
r
o
p
o
s
es
a
UW
AC
M
f
o
r
d
ir
ec
t
a
n
d
v
ar
io
u
s
m
u
ltip
a
th
s
in
th
e
d
ee
p
s
ea
b
ased
o
n
a
p
ass
iv
e
s
o
n
ar
eq
u
atio
n
.
T
h
e
m
o
d
el
lev
er
a
g
es
a
p
ass
iv
e
s
o
n
ar
eq
u
atio
n
to
esti
m
ate
th
e
SNR
[
2
9
]
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
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8
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I
n
t J E
lec
&
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p
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g
,
Vo
l.
14
,
No
.
6
,
Dec
em
b
e
r
20
24
:
6
1
4
8
-
6
1
5
9
6150
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u
r
e
1
.
Pro
p
o
s
ed
UW
AC
M
f
o
r
SAR
o
p
er
atio
n
i
n
d
ee
p
s
ea
Fig
u
r
e
2
.
W
o
r
k
f
lo
w
d
ia
g
r
am
f
o
r
th
e
p
r
o
p
o
s
ed
UW
AC
M
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J E
lec
&
C
o
m
p
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n
g
I
SS
N:
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8
7
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8
A
p
a
s
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ive
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o
n
a
r
b
a
s
ed
u
n
d
erw
a
ter a
co
u
s
tic
ch
a
n
n
el
mo
d
el
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r
imp
r
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…
(
A
fs
a
r
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h
a
med
A
b
b
a
s
)
6151
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q
u
atio
n
(
1
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d
ep
icts
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n
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h
ip
=
−
−
+
(
1
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wh
er
e
(
1
µ
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1
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d
en
o
tes
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e
s
o
u
r
ce
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in
d
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g
th
e
s
o
u
n
d
p
o
we
r
em
itted
b
y
th
e
UL
B
.
T
L
(
d
B
)
s
ig
n
if
ies
th
e
tr
an
s
m
is
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io
n
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s
s
,
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u
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tify
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n
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g
o
f
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h
e
UL
B
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ig
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r
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en
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e
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ac
k
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o
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n
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is
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r
esen
t
in
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e
u
n
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er
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n
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m
en
t.
DI
(
d
B
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r
ep
r
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th
e
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ir
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d
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o
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th
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UL
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tem
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r
s
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n
al.
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h
is
r
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ch
p
r
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r
ities
d
eter
m
in
in
g
T
L
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d
SNR
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o
r
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th
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ir
ec
t
an
d
v
ar
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s
m
u
ltip
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ce
n
ar
io
s
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th
e
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ep
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ab
le
1
p
r
o
v
id
es
s
p
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if
ic
r
ef
er
en
ce
v
alu
es
th
at
wer
e
ad
o
p
te
d
b
ased
o
n
r
e
s
ea
r
ch
[
2
4
]
f
o
r
th
e
d
eter
m
in
atio
n
o
f
T
L
an
d
SNR
in
th
is
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ch
.
T
ab
le
1
.
R
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en
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v
alu
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o
r
,
,
DI
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o
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r
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5
k
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z
2
.
1
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Det
er
m
ina
t
io
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t
ra
ns
m
is
s
io
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s
s
I
n
th
e
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ee
p
-
s
ea
en
v
i
r
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n
m
e
n
t,
th
e
d
eter
m
in
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o
f
tr
an
s
m
i
s
s
io
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lo
s
s
(
T
L
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la
y
s
a
v
ital
r
o
le
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th
e
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lcu
latio
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o
f
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.
Hig
h
T
L
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estricts
th
e
m
ax
im
u
m
d
is
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ce
th
at
en
ab
les
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eliab
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co
m
m
u
n
icatio
n
.
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L
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k
en
s
th
e
s
ig
n
al,
wh
ile
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a
ck
g
r
o
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n
d
n
o
is
e
r
em
ain
s
r
elati
v
ely
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n
s
tan
t.
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h
is
r
ed
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ce
s
th
e
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,
m
ak
in
g
it
h
ar
d
er
t
o
d
em
o
d
u
late
th
e
tr
an
s
m
itted
in
f
o
r
m
atio
n
.
T
h
u
s
,
T
L
d
eter
m
in
atio
n
u
s
in
g
th
e
ch
a
n
n
el
m
o
d
el
h
elp
s
to
en
s
u
r
e
r
eliab
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co
m
m
u
n
icatio
n
.
I
n
th
e
d
ee
p
s
ea
,
T
L
is
p
r
im
ar
ily
r
esp
o
n
s
ib
le
f
o
r
ab
s
o
r
p
ti
o
n
an
d
s
p
r
ea
d
in
g
lo
s
s
es.
T
h
e
s
p
h
er
ical
ex
p
an
s
io
n
o
f
t
h
e
ac
o
u
s
tic
wav
e
as
it
tr
av
els
awa
y
f
r
o
m
th
e
t
r
an
s
m
itter
ca
u
s
es
s
p
r
ea
d
in
g
lo
s
s
in
th
e
d
ee
p
s
ea
.
Ho
wev
er
,
ab
s
o
r
p
tio
n
lo
s
s
p
lay
s
a
m
o
r
e
cr
itical
r
o
le,
co
n
v
e
r
tin
g
s
o
u
n
d
in
te
n
s
ity
in
to
h
ea
t
en
er
g
y
.
T
h
is
lo
s
s
o
cc
u
r
s
in
b
o
t
h
d
ir
ec
t
an
d
m
u
ltip
ath
p
r
o
p
ag
atio
n
p
ath
s
.
E
q
u
atio
n
(
2
)
g
i
v
es
th
e
ab
s
o
r
p
tio
n
co
ef
f
icien
t
co
n
s
id
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in
th
is
p
ap
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p
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tim
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with
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eter
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b
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titu
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ese
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alu
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.
I
n
th
i
s
r
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ch
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b
o
th
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th
is
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o
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p
tio
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co
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f
f
i
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t
v
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I
n
t
h
e
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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2
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I
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t J E
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&
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m
p
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,
Vo
l.
14
,
No
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6
,
Dec
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b
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r
20
24
:
6
1
4
8
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6
1
5
9
6152
f
o
llo
win
g
an
aly
s
is
,
an
d
d
en
o
te
th
e
a
b
s
o
r
p
tio
n
co
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f
f
icien
t
i
n
d
B
/k
m
an
d
th
e
tr
an
s
m
is
s
io
n
r
an
g
e
in
m
eter
s
,
r
esp
ec
tiv
ely
.
T
ab
le
2
.
Simu
latio
n
p
ar
am
eter
s
f
o
r
d
ee
p
-
wate
r
T
L
ca
lcu
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n
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a
r
a
me
t
e
r
s
V
a
l
u
e
s
Te
mp
e
r
a
t
u
r
e
(
T)
2
°
C
S
a
l
i
n
i
t
y
(
S
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3
4
p
p
t
pH
8
2
.
1
.
1
.
T
L
f
o
r
direct
pa
t
h pro
pa
g
a
t
io
n in dee
p wa
t
er
I
n
UAC,
th
e
d
ir
ec
t
p
ath
r
ef
er
s
to
th
e
s
tr
aig
h
t
-
lin
e
tr
ajec
to
r
y
th
r
o
u
g
h
wh
ich
s
o
u
n
d
wav
es
tr
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el
f
r
o
m
th
e
s
o
u
r
ce
t
o
th
e
r
ec
eiv
er
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s
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ite
ap
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r
in
g
to
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th
e
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o
s
t
ef
f
icien
t
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ath
,
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L
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r
s
alo
n
g
t
h
e
d
ir
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t
p
ath
as
a
r
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lt
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d
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s
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n
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r
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t
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ath
p
r
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atio
n
[
3
2
]
as
(
5
)
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=
20
l
og
10
+
10
−
3
(
5
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T
h
e
d
ir
e
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p
at
h
r
e
p
r
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ts
th
e
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l
s
ce
n
ar
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in
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s
an
d
in
ter
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tio
n
s
with
th
e
en
v
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r
o
n
m
e
n
t.
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h
en
th
e
T
L
o
n
th
e
d
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t
p
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m
p
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f
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ated
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2
.
1
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2
.
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f
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m
ultipa
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h pro
pa
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t
io
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t
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R
ea
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tim
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T
L
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m
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r
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SAR
o
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s
.
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h
is
en
ab
les
S
AR
team
s
to
p
r
io
r
itize
s
ea
r
ch
ar
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r
ch
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ts
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ar
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with
lo
we
r
p
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icted
T
L
,
w
h
er
e
th
e
ch
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ce
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o
f
d
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g
s
u
r
v
iv
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r
s
a
r
e
h
i
g
h
er
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h
ile
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is
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g
ch
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n
el
m
o
d
els
in
v
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l
v
e
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o
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co
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lex
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o
r
ith
m
s
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eter
m
in
e
T
L
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th
is
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o
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el
s
im
p
lifie
s
th
is
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r
o
ce
s
s
b
y
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s
in
g
m
ath
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atica
l
eq
u
atio
n
s
to
ca
lcu
late
th
e
T
L
o
f
v
ar
io
u
s
m
u
ltip
ath
s
in
th
e
d
ee
p
s
ea
.
T
h
e
m
u
ltip
ath
s
in
d
ee
p
wate
r
a
r
e
d
u
e
to
SR
,
SD,
B
B
,
C
Z
,
DS
C
,
an
d
R
AP.
I
m
p
lem
en
tin
g
th
e
T
L
e
x
p
r
ess
io
n
s
in
th
ese
p
r
o
p
a
g
atio
n
p
ath
s
allo
ws
u
s
t
o
d
esig
n
th
e
T
L
m
o
d
el
f
o
r
d
e
ep
wate
r
.
T
h
e
f
o
llo
win
g
a
n
aly
s
is
d
em
o
n
s
tr
ates
th
e
T
L
d
eter
m
in
atio
n
f
o
r
th
ese
v
ar
io
u
s
m
u
ltip
ath
p
r
o
p
ag
atio
n
p
ath
s
in
a
d
ee
p
-
wate
r
en
v
ir
o
n
m
en
t.
Kn
o
win
g
th
e
SNR
f
o
r
th
ese
v
ar
io
u
s
m
u
ltip
a
th
p
r
o
p
ag
atio
n
p
ath
s
co
u
l
d
im
p
r
o
v
e
t
h
e
SAR
ap
p
licatio
n
'
s
p
er
f
o
r
m
a
n
ce
.
a.
Su
r
f
ac
e
r
ef
lectio
n
(
SR
)
T
h
e
SR
is
u
s
ed
to
r
ef
er
to
th
e
b
o
u
n
ci
n
g
b
ac
k
o
f
s
o
u
n
d
f
r
o
m
th
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d
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I
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C
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N:
2088
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8
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3
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m
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B
B
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T
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R
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f
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le
cted
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en
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f
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ities
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d
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s
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1
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f
θ
1
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7
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k
Hz,
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d
k
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5
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d.
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Z
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th
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s
ea
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led
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f
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Z
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cu
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e
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t
h
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s
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d
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city
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s
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p
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f
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n
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m
f
o
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m
in
g
.
T
h
e
to
t
al
in
th
e
co
n
v
er
g
e
n
ce
zo
n
e
is
g
iv
en
b
y
(
1
6
)
:
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=
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+
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10
−
3
−
(
1
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)
wh
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th
e
g
ain
,
a
n
d
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etwe
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n
d
2
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B
.
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h
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lo
t
is
o
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tain
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s
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g
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e
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th
e
d
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s
ea
,
with
a
m
in
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u
m
v
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city
at
m
id
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d
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d
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g
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(
SOFAR
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n
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h
is
m
in
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u
m
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city
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s
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d
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r
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lectio
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h
e
f
o
r
a
DSC
is
g
iv
en
b
y
(
1
7
)
:
=
10
0
+
10
+
∗
10
−
3
(
1
7
)
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8
7
0
8
I
n
t J E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
14
,
No
.
6
,
Dec
em
b
e
r
20
24
:
6
1
4
8
-
6
1
5
9
6154
wh
er
e
0
is
th
e
cy
lin
d
r
ical
to
s
p
h
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ical
s
p
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g
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n
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d
is
d
e
f
in
ed
as
(
1
8
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,
0
=
(
8
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(
)
1
2
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(
1
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in
wh
ich
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s
k
ip
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is
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ce
,
is
th
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e
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th
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n
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iv
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:
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1
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n
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l
ex
ten
t,
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th
e
m
a
x
im
u
m
c
h
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n
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u
n
d
s
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d
,
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n
d
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th
e
d
if
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er
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ce
b
etwe
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d
th
e
s
o
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d
s
p
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d
o
n
th
e
ch
an
n
el
ax
is
.
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n
th
is
an
aly
s
is
,
th
e
p
ar
am
eter
s
co
n
s
id
er
ed
a
r
e
=
3
7
.
5
k
Hz,
=
1
,
5
0
0
m
/s
,
=
1
0
0
m
/s
,
=
1
,
500
m
/s
an
d
=
1
,
5
0
0
m
/s
,
an
d
=
= 3
,
0
0
0
m
ete
r
s
.
f.
R
eliab
le
ac
o
u
s
tic
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ath
(
R
AP)
I
f
th
e
tr
an
s
m
itter
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in
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e
d
ee
p
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h
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u
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wh
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lan
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3.
RE
SU
L
T
S AN
D
D
I
SCU
SS
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O
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Fo
r
th
e
SAR
ap
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L
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d
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e
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cial
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AC
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ar
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eter
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ate.
A
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icate
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ig
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ier
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etec
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q
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atio
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eter
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in
es
th
e
SNR
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th
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el.
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h
e
T
L
v
s
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r
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g
e
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is
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d
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n
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s
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d
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2
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T
ra
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m
is
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io
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s
v
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ra
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Fig
u
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an
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o
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at
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e
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in
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r
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th
e
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L
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cr
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s
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T
h
o
u
g
h
th
e
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s
o
r
p
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ee
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r
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en
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m
p
a
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ed
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s
h
al
lo
w
wate
r
,
th
e
T
L
is
h
ig
h
er
i
n
d
ee
p
wate
r
d
u
e
to
s
p
h
er
ical
s
p
r
ea
d
in
g
.
T
h
e
d
eter
m
in
atio
n
o
f
T
L
v
alu
es
h
elp
s
to
f
in
d
SNR
f
o
r
v
ar
io
u
s
UAC a
p
p
licatio
n
s
.
T
h
e
T
L
f
o
r
s
u
r
f
ac
e
r
ef
lectio
n
m
u
ltip
ath
p
r
o
p
ag
atio
n
in
cr
ea
s
es
as
th
e
r
an
g
e
in
cr
ea
s
es.
I
t
is
b
ased
o
n
th
e
o
p
e
r
atin
g
f
r
eq
u
en
cy
,
win
d
s
p
ee
d
,
an
d
g
r
az
in
g
an
g
le.
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ased
o
n
th
e
o
p
er
atin
g
f
r
e
q
u
en
cy
,
m
ix
ed
lay
er
d
ep
th
,
an
d
tem
p
er
atu
r
e,
s
u
r
f
ac
e
d
u
ct
T
L
in
cr
ea
s
es
as
th
e
r
an
g
e
in
cr
ea
s
es.
T
h
e
T
L
f
o
r
lo
n
g
r
an
g
es
is
v
er
y
h
ig
h
in
s
u
r
f
ac
e
d
u
ct
e
n
v
ir
o
n
m
en
ts
.
Dep
en
d
in
g
o
n
th
e
o
p
er
a
tin
g
f
r
eq
u
en
cy
a
n
d
b
o
tto
m
ty
p
es,
th
er
e
is
a
co
n
s
id
er
ab
le
tr
a
n
s
m
is
s
io
n
lo
s
s
v
ar
iatio
n
f
o
r
a
b
o
tto
m
b
o
u
n
ce
,
s
an
d
y
b
o
tto
m
,
clay
ed
m
u
d
,
m
u
d
d
y
v
er
y
f
in
e
s
an
d
,
an
d
s
an
d
-
m
u
d
-
clay
m
u
lt
ip
ath
p
r
o
p
a
g
atio
n
o
f
d
ee
p
wat
er
.
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o
m
p
a
r
ed
with
all
th
e
o
th
e
r
ca
s
es,
th
e
b
o
tto
m
b
o
u
n
ce
T
L
is
h
ig
h
f
o
r
lo
n
g
r
a
n
g
es.
B
ased
o
n
th
e
o
p
e
r
atin
g
f
r
eq
u
e
n
cy
an
d
co
n
v
er
g
en
ce
z
o
n
e
g
ain
,
t
h
er
e
is
an
in
cr
ea
s
e
in
T
L
f
o
r
in
cr
ea
s
ed
r
a
n
g
es f
o
r
a
co
n
v
er
g
en
ce
m
u
ltip
ath
p
r
o
p
a
g
atio
n
o
f
d
ee
p
wate
r
.
Dep
en
d
in
g
o
n
th
e
o
p
er
atin
g
f
r
eq
u
en
cy
,
s
p
ee
d
o
f
s
o
u
n
d
,
an
d
d
e
p
th
o
f
s
o
u
r
c
e
an
d
r
ec
eiv
er
,
t
h
er
e
is
an
in
cr
ea
s
e
in
T
L
f
o
r
in
cr
ea
s
ed
r
an
g
es
f
o
r
DSC
m
u
ltip
ath
p
r
o
p
ag
atio
n
o
f
d
ee
p
w
ater
.
T
h
e
o
p
er
atin
g
f
r
e
q
u
en
c
y
an
d
r
an
g
e
b
etwe
en
s
o
u
r
ce
an
d
r
ec
eiv
er
i
n
R
AP in
cr
ea
s
e
T
L
f
o
r
i
n
cr
ea
s
ed
r
an
g
es.
T
h
u
s
,
SAR
o
p
er
atio
n
s
s
h
o
u
ld
p
r
io
r
itize
p
ath
s
with
lo
wer
T
L
f
o
r
co
m
m
u
n
icatio
n
.
Ad
ju
s
tm
en
ts
to
tr
an
s
m
itter
p
o
wer
an
d
r
ec
ei
v
er
s
en
s
itiv
ity
ar
e
ess
en
tial
to
co
m
p
en
s
ate
f
o
r
h
ig
h
er
T
L
in
ce
r
tain
p
ath
s
,
p
ar
ticu
lar
ly
f
o
r
s
u
r
f
ac
e
r
e
f
lectio
n
an
d
b
o
tto
m
b
o
u
n
ce
s
ce
n
ar
io
s
.
Un
d
e
r
s
tan
d
in
g
th
e
im
p
ac
t
o
f
th
e
s
ea
f
lo
o
r
ty
p
e
an
d
wate
r
s
u
r
f
ac
e
co
n
d
itio
n
s
o
n
T
L
h
el
p
s
in
p
la
n
n
in
g
SAR
o
p
er
atio
n
s
m
o
r
e
ef
f
ec
tiv
el
y
,
en
s
u
r
i
n
g
r
o
b
u
s
t
co
m
m
u
n
icatio
n
an
d
d
etec
tio
n
s
tr
ateg
ies.
I
n
co
r
p
o
r
atin
g
m
u
l
tip
le
p
r
o
p
a
g
atio
n
p
ath
s
in
to
t
h
e
co
m
m
u
n
icatio
n
s
tr
ateg
y
en
s
u
r
es
r
ed
u
n
d
a
n
cy
an
d
f
lex
ib
ilit
y
,
cr
u
cial
f
o
r
h
an
d
lin
g
d
y
n
am
ic
an
d
ch
al
len
g
in
g
d
ee
p
-
wate
r
en
v
ir
o
n
m
en
ts
.
3
.
2
.
Sig
na
l
-
to
-
no
is
e
ra
t
io
v
s
ra
ng
e
a
na
ly
s
is
T
h
e
SNR
is
ca
lcu
lated
f
o
r
d
ee
p
-
wate
r
d
ir
ec
t
a
n
d
m
u
ltip
ath
p
r
o
p
ag
atio
n
an
d
is
s
h
o
wn
in
T
a
b
le
4
.
I
t
is
ev
alu
ated
f
o
r
a
d
e
p
th
o
f
3
,
0
0
0
m
,
at
an
o
p
er
atin
g
f
r
eq
u
en
cy
o
f
3
7
.
5
k
Hz,
SL=
1
6
0
.
5
d
B
,
N
L
=6
1
d
B
,
DI
=0
d
B
,
an
d
th
e
ca
lcu
lated
v
alu
es
o
f
T
L
p
r
o
v
id
ed
in
T
ab
le
3
.
T
h
ese
p
ar
am
eter
s
ar
e
cr
itical
f
o
r
ac
cu
r
ate
SNR
co
m
p
u
tatio
n
.
T
h
e
ca
lc
u
lated
SNR
v
alu
es p
r
o
v
id
e
in
s
ig
h
ts
in
t
o
s
ig
n
al
d
etec
tab
ilit
y
.
T
ab
le
4
.
SNR
ca
lcu
latio
n
f
o
r
d
ir
ec
t a
n
d
v
a
r
io
u
s
m
u
ltip
ath
p
r
o
p
ag
atio
n
o
f
d
ee
p
-
wate
r
R
a
n
g
e
(
m)
D
i
r
e
c
t
p
a
t
h
S
N
R
(
d
B
)
M
u
l
t
i
p
a
t
h
S
N
R
(
d
B
)
SR
SD
BB
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SB
BB
-
CM
BB
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M
V
F
S
BB
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S
M
C
CZ
D
S
C
R
A
P
1
0
0
5
8
.
5
4
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.
5
4
9
.
5
5
2
.
5
4
0
.
5
4
6
.
5
5
0
.
5
7
8
.
5
4
5
.
5
5
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.
5
5
0
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4
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5
3
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5
6
2
.
5
3
6
.
5
4
2
.
5
1
0
0
0
3
2
.
5
2
1
.
5
2
5
.
5
1
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.
5
-
1
.
5
4
.
5
8
.
5
5
2
.
5
2
9
.
5
3
2
.
5
3
0
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.
5
-
1
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.
5
-
5
0
.
5
-
6
2
.
5
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5
6
.
5
-
5
2
.
5
3
0
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5
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5
1
0
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5
5
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-
7
.
5
-
1
8
.
5
-
4
5
.
5
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1
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5
.
5
-
1
1
7
.
5
-
1
1
1
.
5
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1
0
7
.
5
1
2
.
5
-
3
.
5
-
7
.
5
8
0
0
0
-
3
1
.
5
-
4
2
.
5
-
9
4
.
5
-
1
8
5
.
5
-
1
9
7
.
5
-
1
9
1
.
5
-
1
8
7
.
5
-
1
1
.
5
-
2
5
.
5
-
3
1
.
5
1
0
,
0
0
0
-
4
6
.
5
-
5
7
.
5
-
1
2
7
.
5
-
2
3
7
.
5
-
2
4
9
.
5
-
2
4
3
.
5
-
2
3
9
.
5
-
2
8
.
5
-
3
9
.
5
-
4
6
.
5
Fig
u
r
e
4
p
r
o
v
id
es
v
alu
ab
le
in
s
ig
h
ts
in
to
th
e
SNR
f
o
r
b
o
th
d
ir
ec
t
p
ath
an
d
v
ar
i
o
u
s
m
u
ltip
ath
p
r
o
p
a
g
atio
n
s
ce
n
ar
io
s
in
d
ee
p
-
wate
r
en
v
ir
o
n
m
en
ts
.
As
ex
p
e
cted
,
d
u
e
to
s
ig
n
al
atten
u
atio
n
o
v
er
d
is
tan
ce
,
t
h
e
SNR
d
ec
r
ea
s
es
as
th
e
r
an
g
e
in
cr
ea
s
es.
All
s
ce
n
ar
io
s
c
o
n
s
is
ten
tly
o
b
s
er
v
e
th
is
tr
e
n
d
.
Dif
f
er
en
t
m
u
ltip
ath
s
ce
n
ar
io
s
ex
h
ib
it
d
is
tin
ct
p
att
er
n
s
o
f
s
ig
n
al
atten
u
atio
n
c
o
m
p
ar
ed
to
th
e
d
ir
ec
t
p
ath
.
M
u
ltip
ath
s
s
u
ch
as
SR
,
SD,
an
d
B
B
,
lead
to
ad
d
itio
n
al
s
ig
n
al
d
eg
r
ad
atio
n
,
r
esu
ltin
g
in
lo
wer
SNR
v
alu
es.
E
n
v
i
r
o
n
m
en
tal
f
ac
t
o
r
s
,
s
u
ch
as seab
ed
co
m
p
o
s
itio
n
an
d
wate
r
d
ep
th
,
p
lay
a
n
im
p
o
r
tan
t r
o
le
in
s
h
ap
i
n
g
th
e
p
r
o
p
ag
at
io
n
ch
ar
ac
ter
is
tics
an
d
s
ig
n
al
q
u
ality
.
Fo
r
in
s
ta
n
ce
,
s
ce
n
ar
io
s
in
v
o
l
v
in
g
b
o
tt
o
m
b
o
u
n
ce
o
n
d
if
f
e
r
en
t
ty
p
e
s
o
f
s
ea
b
ed
s
s
h
o
w
v
ar
y
in
g
d
eg
r
ee
s
o
f
s
ig
n
al
atte
n
u
atio
n
.
T
h
e
co
n
v
er
g
en
ce
z
o
n
e
s
ce
n
ar
io
d
em
o
n
s
tr
ates
a
u
n
i
q
u
e
b
e
h
av
io
r
wh
er
e
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8
7
0
8
I
n
t J E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
14
,
No
.
6
,
Dec
em
b
e
r
20
24
:
6
1
4
8
-
6
1
5
9
6156
th
e
SNR
in
itially
in
cr
ea
s
es
with
r
an
g
e
b
ef
o
r
e
d
ec
r
ea
s
in
g
ag
ain
.
T
h
is
b
eh
av
io
r
is
ch
ar
ac
ter
is
tic
o
f
th
e
co
n
v
er
g
en
ce
o
f
ac
o
u
s
tic
r
ay
s
at
s
p
ec
if
ic
d
ep
th
s
,
lead
i
n
g
to
en
h
an
ce
d
s
ig
n
al
s
tr
en
g
th
with
in
th
e
co
n
v
er
g
en
ce
zo
n
e.
T
h
e
d
ee
p
s
o
u
n
d
ch
a
n
n
el
s
ce
n
ar
io
ex
h
ib
its
r
elativ
ely
s
tab
le
SN
R
v
alu
es
ac
r
o
s
s
d
if
f
er
en
t
r
an
g
es
co
m
p
ar
ed
to
o
t
h
er
s
ce
n
ar
io
s
.
T
h
is
in
d
icate
s
th
e
p
r
esen
ce
o
f
a
d
ee
p
s
o
u
n
d
c
h
an
n
el
wh
er
e
ac
o
u
s
tic
s
ig
n
als
p
r
o
p
a
g
ate
with
m
in
im
al
atten
u
atio
n
,
r
esu
ltin
g
in
co
n
s
is
ten
t SNR
v
alu
es o
v
er
d
is
tan
ce
.
Fig
u
r
e
4
.
SNR
f
o
r
d
ir
ec
t a
n
d
v
ar
io
u
s
m
u
ltip
ath
p
r
o
p
a
g
atio
n
o
f
d
ee
p
-
wate
r
Fig
u
r
e
5
d
is
p
lay
s
SNR
co
m
p
ar
is
o
n
o
f
p
r
o
p
o
s
ed
a
n
d
ex
is
tin
g
[
2
4
]
UW
AC
M
f
o
r
d
ir
ec
t
p
ath
p
r
o
p
a
g
atio
n
o
f
d
ee
p
-
wate
r
at
a
d
ep
th
o
f
3
,
000
m
.
T
h
e
p
r
o
p
o
s
ed
UW
AC
M
s
ig
n
if
ican
tly
o
u
tp
er
f
o
r
m
s
th
e
ex
is
tin
g
m
o
d
el
in
te
r
m
s
o
f
SNR
f
o
r
d
ir
ec
t
p
ath
p
r
o
p
ag
atio
n
at
all
test
ed
r
an
g
es
(
1
0
0
to
1
0
,
0
0
0
m
ete
r
s
)
.
T
h
e
p
r
o
p
o
s
ed
m
o
d
el
c
o
n
s
is
ten
tly
ex
h
ib
its
h
ig
h
er
SNR
v
alu
es,
in
d
icatin
g
b
etter
s
ig
n
al
tr
an
s
m
is
s
io
n
q
u
ality
an
d
im
p
r
o
v
e
d
n
o
is
e
m
itig
atio
n
.
T
h
is
en
h
an
ce
m
en
t
is
cr
u
cial
f
o
r
ap
p
licatio
n
s
s
u
ch
as
b
lack
b
o
x
d
etec
tio
n
an
d
s
ea
r
ch
an
d
r
escu
e
o
p
er
atio
n
s
in
d
ee
p
s
ea
en
v
ir
o
n
m
en
ts
.
Fig
u
r
e
5
.
SNR
co
m
p
ar
is
o
n
o
f
p
r
o
p
o
s
ed
an
d
e
x
is
tin
g
UW
AC
M
f
o
r
d
ir
ec
t
p
ath
p
r
o
p
a
g
atio
n
o
f
d
ee
p
-
wate
r
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J E
lec
&
C
o
m
p
E
n
g
I
SS
N:
2088
-
8
7
0
8
A
p
a
s
s
ive
s
o
n
a
r
b
a
s
ed
u
n
d
erw
a
ter a
co
u
s
tic
ch
a
n
n
el
mo
d
el
fo
r
imp
r
o
ve
d
…
(
A
fs
a
r
A
li Mo
h
a
med
A
b
b
a
s
)
6157
Un
d
er
s
tan
d
in
g
th
e
d
if
f
e
r
en
t
p
r
o
p
ag
atio
n
p
ath
s
h
elp
s
in
p
lan
n
in
g
t
h
e
o
p
er
atio
n
al
r
an
g
e
a
n
d
ch
o
o
s
in
g
th
e
ap
p
r
o
p
r
iate
c
o
m
m
u
n
icatio
n
s
y
s
tem
s
.
Fo
r
in
s
tan
ce
,
k
n
o
win
g
th
at
c
o
n
v
e
r
g
en
ce
zo
n
es
an
d
d
ee
p
s
o
u
n
d
ch
an
n
els
s
u
p
p
o
r
t
lo
n
g
e
r
r
an
g
es
allo
ws
f
o
r
s
tr
ateg
ic
d
ep
lo
y
m
en
t
o
f
ass
ets.
Ar
ea
s
with
ex
p
ec
ted
lo
w
SNR
(
e.
g
.
,
ce
r
tain
b
o
tto
m
b
o
u
n
ce
p
ath
s
)
ca
n
b
e
id
e
n
tifie
d
as
c
h
al
len
g
in
g
f
o
r
co
m
m
u
n
icatio
n
,
p
r
o
m
p
tin
g
th
e
n
ee
d
f
o
r
alter
n
ativ
e
m
eth
o
d
s
o
r
m
o
r
e
f
r
e
q
u
en
t
r
elay
p
o
in
ts
.
C
h
o
o
s
in
g
th
e
r
ig
h
t
ac
o
u
s
ti
c
eq
u
ip
m
en
t
(
e.
g
.
,
tr
an
s
d
u
ce
r
s
,
r
ec
eiv
er
s
)
th
at
ca
n
o
p
tim
ize
th
e
SNR
f
o
r
s
p
ec
if
ic
p
ath
s
will
im
p
r
o
v
e
th
e
ef
f
i
cien
cy
an
d
s
u
cc
ess
r
ate
o
f
SAR
o
p
er
atio
n
s
.
SAR
t
ea
m
s
ca
n
ad
ap
t th
eir
s
tr
ateg
ies b
ased
o
n
th
e
en
v
ir
o
n
m
en
tal
c
h
ar
ac
ter
is
tics
(
e.
g
.
,
b
o
tto
m
ty
p
e,
p
r
esen
ce
o
f
d
u
ct
s
)
,
en
s
u
r
in
g
b
etter
p
r
ep
ar
ed
n
e
s
s
an
d
r
esp
o
n
s
e
in
d
if
f
er
en
t
d
ee
p
-
s
ea
s
ce
n
ar
io
s
.
T
h
u
s
,
th
e
SNR
r
esu
lts
p
r
o
v
id
e
a
d
etailed
u
n
d
er
s
tan
d
in
g
o
f
h
o
w
d
if
f
er
e
n
t
ac
o
u
s
tic
p
r
o
p
ag
atio
n
p
ath
s
p
er
f
o
r
m
in
a
d
ee
p
-
s
ea
en
v
ir
o
n
m
en
t,
d
ir
ec
tly
in
f
l
u
en
cin
g
th
e
s
tr
at
eg
ies
an
d
e
f
f
ec
tiv
en
ess
o
f
s
ea
r
ch
an
d
r
escu
e
o
p
er
atio
n
s
.
Un
d
er
s
tan
d
in
g
th
e
v
ar
iatio
n
s
in
SNR
u
n
d
er
d
if
f
er
en
t
p
r
o
p
a
g
atio
n
s
ce
n
ar
io
s
is
cr
u
cial
f
o
r
d
esig
n
in
g
r
o
b
u
s
t
u
n
d
er
wate
r
co
m
m
u
n
ica
tio
n
s
y
s
tem
s
s
u
ch
as
SAR
ap
p
licatio
n
s
.
T
h
e
s
p
ec
if
ic
en
v
ir
o
n
m
en
tal
co
n
d
itio
n
s
en
co
u
n
ter
e
d
in
d
ee
p
-
wate
r
en
v
ir
o
n
m
e
n
ts
s
h
o
u
ld
tailo
r
s
tr
ateg
ies
f
o
r
m
itig
atin
g
m
u
ltip
at
h
in
ter
f
er
en
ce
an
d
o
p
tim
izin
g
s
ig
n
al
tr
a
n
s
m
is
s
io
n
.
Ov
er
all,
th
e
f
in
d
i
n
g
s
u
n
d
er
s
co
r
e
th
e
c
o
m
p
lex
ity
o
f
s
o
u
n
d
p
r
o
p
a
g
atio
n
in
d
ee
p
o
ce
an
s
ce
n
ar
io
s
an
d
h
ig
h
lig
h
t
th
e
im
p
o
r
tan
ce
o
f
c
o
n
s
id
er
in
g
m
u
ltip
ath
ef
f
ec
ts
wh
en
d
esig
n
in
g
an
d
d
e
p
lo
y
in
g
u
n
d
er
wate
r
co
m
m
u
n
icatio
n
s
y
s
tem
s
.
T
h
ese
f
in
d
in
g
s
o
f
th
e
m
o
d
el
in
tr
o
d
u
ce
d
in
th
is
p
ap
er
clo
s
ely
alig
n
with
ex
is
tin
g
liter
atu
r
e
[
2
2
]
,
[
2
4
]
,
d
em
o
n
s
tr
atin
g
a
h
ig
h
lev
el
o
f
c
o
n
s
is
ten
cy
an
d
v
alid
atio
n
.
4.
CO
NCLU
SI
O
N
T
h
i
s
p
ap
e
r
in
tr
o
d
u
ce
s
an
u
n
d
er
w
at
er
ac
o
u
s
ti
c
ch
an
n
el
m
o
d
el
b
a
s
ed
o
n
th
e
p
a
s
s
iv
e
s
o
n
ar
e
q
u
a
tio
n
m
eth
o
d
,
s
p
e
ci
f
i
ca
lly
t
ai
lo
r
ed
f
o
r
d
e
ep
-
s
e
a
en
v
ir
o
n
m
en
t
s
an
d
ta
r
g
e
ted
to
war
d
s
S
A
R
o
p
er
at
io
n
s
.
T
h
e
m
o
d
e
l
ad
d
r
e
s
s
e
s
th
e
ch
a
ll
en
g
e
s
p
o
s
e
d
b
y
h
ig
h
T
L
,
m
u
l
tip
ath
p
r
o
p
ag
at
io
n
,
a
n
d
am
b
i
en
t
n
o
i
s
e,
wh
i
ch
s
ig
n
i
f
i
ca
n
tly
im
p
a
ct
th
e
SN
R
an
d
co
m
m
u
n
ica
t
io
n
e
f
f
e
ct
iv
en
e
s
s
in
d
ee
p
-
s
ea
s
c
en
ar
io
s
.
B
y
f
o
cu
s
in
g
o
n
ch
a
r
ac
te
r
i
zin
g
SN
R
t
h
r
o
u
g
h
an
in
-
d
ep
th
an
a
ly
s
i
s
o
f
T
L
f
o
r
v
ar
io
u
s
m
u
l
ti
p
ath
p
r
o
p
ag
a
tio
n
m
o
d
e
s
,
in
c
l
u
d
in
g
S
R
,
SD
,
B
B
,
C
Z
,
D
S
C
,
an
d
R
A
P,
th
is
wo
r
k
f
il
l
s
a
cr
i
ti
ca
l
g
ap
in
e
x
i
s
tin
g
li
ter
atu
r
e
b
y
p
r
o
v
id
in
g
co
m
p
r
eh
en
s
iv
e
in
s
ig
h
t
s
in
to
SN
R
d
e
te
r
m
i
n
a
tio
n
r
e
le
v
an
t
to
SA
R
a
p
p
l
ic
at
io
n
s
.
T
h
e
p
r
o
p
o
s
e
d
m
o
d
e
l
aim
s
to
q
u
a
n
tify
th
e
d
e
te
ct
io
n
ca
p
ab
i
li
ti
e
s
o
f
U
L
B
s
u
n
d
er
d
iv
er
s
e
d
ee
p
-
s
ea
s
ce
n
a
r
io
s
a
n
d
co
n
f
ig
u
r
a
tio
n
s
,
th
u
s
o
f
f
er
in
g
v
alu
ab
l
e
in
s
ig
h
t
s
f
o
r
im
p
r
o
v
in
g
U
L
B
p
er
f
o
r
m
a
n
ce
a
n
d
en
h
an
c
in
g
SA
R
o
p
er
at
io
n
s
ef
f
ic
ien
cy
.
T
h
r
o
u
g
h
r
ig
o
r
o
u
s
an
a
ly
s
i
s
an
d
v
al
id
a
tio
n
ag
ain
s
t
ex
i
s
t
in
g
l
it
er
a
tu
r
e,
th
e
a
cc
u
r
ac
y
o
f
th
e
p
r
o
p
o
s
ed
m
o
d
el
i
s
co
n
f
ir
m
ed
,
b
o
l
s
t
er
in
g
i
t
s
u
ti
li
ty
an
d
r
e
l
iab
il
ity
in
p
r
a
ct
ic
al
ap
p
li
ca
tio
n
s
.
Ov
er
a
l
l,
th
i
s
r
e
s
e
a
r
ch
co
n
tr
ib
u
te
s
s
ig
n
i
f
ic
an
tly
t
o
th
e
ad
v
an
c
em
en
t
o
f
u
n
d
er
wa
ter
ac
o
u
s
t
ic
ch
a
n
n
el
m
o
d
e
l
,
p
ar
t
icu
la
r
ly
in
th
e
co
n
tex
t
o
f
S
A
R
o
p
er
at
io
n
s
in
d
ee
p
-
s
ea
en
v
ir
o
n
m
en
t
s
.
T
h
e
in
s
ig
h
ts
g
ain
ed
f
r
o
m
th
is
r
e
s
e
ar
ch
h
av
e
th
e
p
o
ten
ti
al
to
in
f
o
r
m
th
e
d
e
s
ig
n
an
d
d
ep
lo
y
m
en
t
o
f
U
A
C
s
y
s
tem
s
an
d
im
p
r
o
v
e
th
e
ef
f
ec
t
iv
en
e
s
s
o
f
SA
R
m
i
s
s
io
n
s
,
u
l
tim
at
ely
co
n
tr
ib
u
t
in
g
to
en
h
an
c
ed
s
af
e
ty
an
d
s
e
cu
r
ity
i
n
m
ar
it
im
e
en
v
ir
o
n
m
en
t
s
.
Fu
t
u
r
e
wo
r
k
co
u
l
d
f
o
cu
s
o
n
ex
t
e
n
d
in
g
th
e
p
r
o
p
o
s
e
d
m
o
d
el
t
o
in
co
r
p
o
r
a
te
d
y
n
am
i
c
en
v
ir
o
n
m
en
ta
l
f
ac
to
r
s
an
d
r
ea
l
-
t
im
e
d
a
ta
a
s
s
i
m
i
la
tio
n
f
o
r
en
h
a
n
ce
d
a
cc
u
r
ac
y
in
SN
R
p
r
ed
ic
tio
n
.
ACK
NO
WL
E
DG
M
E
N
T
T
h
e
au
t
h
o
r
s
wo
u
ld
lik
e
to
th
a
n
k
th
e
Natio
n
al
I
n
s
titu
te
o
f
O
ce
an
T
ec
h
n
o
lo
g
y
(
NI
OT
)
,
C
h
en
n
ai
f
o
r
p
r
o
v
id
i
n
g
s
u
p
p
o
r
t to
p
er
f
o
r
m
t
h
is
r
esear
ch
wo
r
k
.
RE
F
E
R
E
NC
E
S
[
1
]
M
.
S
t
o
j
a
n
o
v
i
c
,
“
U
n
d
e
r
w
a
t
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r
w
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r
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l
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ss
c
o
m
mu
n
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c
a
t
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o
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s
:
c
u
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t
s
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s,
”
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EEE
O
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a
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c
En
g
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ri
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g
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o
c
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w
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.
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2
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p
p
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,
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0
0
6
.
[
2
]
I
.
F
.
A
k
y
i
l
d
i
z
,
D
.
P
o
m
p
i
l
i
,
a
n
d
T.
M
e
l
o
d
i
a
,
“
U
n
d
e
r
w
a
t
e
r
a
c
o
u
st
i
c
se
n
s
o
r
n
e
t
w
o
r
k
s
:
r
e
se
a
r
c
h
c
h
a
l
l
e
n
g
e
s,
”
A
d
H
o
c
N
e
t
w
o
rks
,
v
o
l
.
3
,
n
o
.
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,
p
p
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2
5
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7
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,
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a
y
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/
j
.
a
d
h
o
c
.
2
0
0
5
.
0
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.
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0
4
.
[
3
]
I
.
F
.
A
k
y
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l
d
i
z
,
D
.
P
o
m
p
i
l
i
,
a
n
d
T
.
M
e
l
o
d
i
a
,
“
C
h
a
l
l
e
n
g
e
s
f
o
r
e
f
f
i
c
i
e
n
t
c
o
m
mu
n
i
c
a
t
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o
n
i
n
u
n
d
e
r
w
a
t
e
r
a
c
o
u
s
t
i
c
se
n
so
r
n
e
t
w
o
r
k
s,”
AC
M
S
I
G
BED
Re
v
i
e
w
,
v
o
l
.
1
,
n
o
.
2
,
p
p
.
3
–
8
,
J
u
l
.
2
0
0
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,
d
o
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:
1
0
.
1
1
4
5
/
1
1
2
1
7
7
6
.
1
1
2
1
7
7
9
.
[
4
]
K
.
M
.
A
w
a
n
,
P
.
A
.
S
h
a
h
,
K
.
I
q
b
a
l
,
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.
G
i
l
l
a
n
i
,
W
.
A
h
ma
d
,
a
n
d
Y
.
N
a
m,
“
U
n
d
e
r
w
a
t
e
r
w
i
r
e
l
e
ss
se
n
s
o
r
n
e
t
w
o
r
k
s
:
a
r
e
v
i
e
w
o
f
r
e
c
e
n
t
i
ssu
e
s
a
n
d
c
h
a
l
l
e
n
g
e
s,”
Wi
re
l
e
ss
C
o
m
m
u
n
i
c
a
t
i
o
n
s
a
n
d
Mo
b
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l
e
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l
.
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9
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–
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,
Ja
n
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9
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o
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0
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9
.
[
5
]
H
.
Esm
a
i
e
l
a
n
d
D
.
J
i
a
n
g
,
“
R
e
v
i
e
w
a
r
t
i
c
l
e
:
m
u
l
t
i
c
a
r
r
i
e
r
c
o
mm
u
n
i
c
a
t
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o
n
f
o
r
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n
d
e
r
w
a
t
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r
a
c
o
u
st
i
c
c
h
a
n
n
e
l
,
”
I
n
t
e
r
n
a
t
i
o
n
a
l
J
o
u
r
n
a
l
o
f
C
o
m
m
u
n
i
c
a
t
i
o
n
s,
N
e
t
w
o
r
k
a
n
d
S
y
st
e
m
S
c
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e
n
c
e
s
,
v
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l
.
0
6
,
n
o
.
0
8
,
p
p
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3
6
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–
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7
6
,
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0
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3
,
d
o
i
:
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0
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2
3
6
/
i
j
c
n
s.
2
0
1
3
.
6
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9
.
[
6
]
M
.
F
.
A
l
i
,
D
.
N
.
K
.
J
a
y
a
k
o
d
y
,
Y
.
A
.
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h
u
r
si
n
,
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.
A
f
f
e
s
,
a
n
d
S
.
D
mi
t
r
y
,
“
R
e
c
e
n
t
a
d
v
a
n
c
e
s
a
n
d
f
u
t
u
r
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d
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c
t
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o
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o
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n
d
e
r
w
a
t
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r
w
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r
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l
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s
s
c
o
mm
u
n
i
c
a
t
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o
n
s
,
”
Arc
h
i
v
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f
C
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m
p
u
t
a
t
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o
n
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l
M
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E
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,
v
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l
.
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7
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.
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p
.
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,
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o
i
:
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7
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s
1
1
8
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1
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0
1
9
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3
5
4
-
8.
[
7
]
C
.
M
.
G
.
G
u
ss
e
n
,
P
.
S
.
R
.
D
i
n
i
z
,
M
.
L.
R
.
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a
m
p
o
s
,
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.
A
.
M
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r
t
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n
s
,
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.
M
.
C
o
s
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a
,
a
n
d
J.
N
.
G
o
i
s
,
“
A
s
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y
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f
u
n
d
e
r
w
a
t
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r
w
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r
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mm
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n
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c
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t
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t
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c
h
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l
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g
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s
,
”
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o
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m
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n
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c
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t
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,
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1
4
2
0
9
/
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c
i
s.
2
0
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6
.
2
2
.
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