TELKOM
NIKA Indonesia
n
Journal of
Electrical En
gineering
Vol. 12, No. 11, Novembe
r
2014, pp. 75
4
3
~ 754
8
DOI: 10.115
9
1
/telkomni
ka.
v
12i11.61
23
7543
Re
cei
v
ed Ap
ril 21, 2014; Revi
sed
Jun
e
23, 2014; Accepted July 2
0
,
2014
The Influence of Aspect Ratio and Orientation to
Scattering Properties of Ellipsoid Ice Particles
Jinhu Wa
ng*
1,2
, Junxiang Ge
1,2
, Ming
Wei
1,2
1
Jiangs
u
Ke
y
L
abor
ator
y
of
Meteoro
l
og
ica
l
Observati
on a
n
d
Information Pr
ocessi
ng,
Nanj
in
g Univ
er
sit
y
of Informati
on Scie
nce a
n
d
T
e
chnolo
g
y
,
Nanj
in
g 21
004
4, china
2
Ke
y
L
abor
ator
y for Aeros
o
l-C
l
ou
d-Preci
p
itat
i
on of Chi
na Me
teorol
ogic
a
l Ad
ministratio
n
，
Nanj
in
g Univ
er
sit
y
of Informati
on Scie
nce a
n
d
T
e
chnolo
g
y
,
Nanj
in
g 21
004
4, china
*Corres
p
o
ndi
n
g
author, em
ail
:
goldtig
er
w
a
ng
@nuist.e
du.cn
A
b
st
r
a
ct
T
he influ
ence
of aspect ratio
and ori
entatio
n to sca
ttering
properti
es of elli
pso
i
d ice p
a
r
ticles at
94GH
z
is
stu
d
ie
d by
Discr
ete-Di
pol
e Ap
proxi
m
ati
o
n
(D
DA) meth
od. Absorpti
on efficiency,
sc
atteri
n
g
efficiency, asy
m
metry factor
and
backsca
tte
ring effici
ency
are co
mputed
w
i
th aspect rati
os vary fro
m
0.
2 t
o
1.0, w
hose si
z
e
par
a
m
eter
rang
e ar
e se
l
e
cted fro
m
0
to 5. It is fou
nd th
at the v
a
lues
of scatter
i
n
g
prop
erties
are
incr
easi
n
g
if
the p
a
rt
icle
si
z
e
i
n
creas
es,
but if th
e s
i
z
e
is
larg
er th
a
n
the
li
mit va
l
ue,
oscill
atio
n occ
u
r, an
d the
os
cillati
on
ph
en
o
m
e
n
o
n
w
ill
be
smo
o
the
d
by
r
and
o
m
or
ientat
ion c
o
mp
ared
w
i
th
that of hor
i
z
o
n
t
a
l or
ientati
on
b
e
caus
e scatteri
ng pr
op
erties c
o
mpute
d
by
r
a
ndo
m orie
ntati
on meth
od hav
e
mor
e
av
era
g
e
frequ
ency th
an th
at of h
o
r
i
z
o
n
ta
l or
ient
ation. In
no
n-
oscill
atin
g re
gi
on, the
scatte
rin
g
efficiency is l
a
r
ger than th
e a
b
sorpti
on effici
ency du
e to
sma
ll i
m
a
g
i
nary
part of the comp
lex refractiv
e
o
f
ice at 9
4
GH
z
,
an
d scatteri
ng pr
operti
es
incre
a
se if
the
aspect rati
o i
n
creas
es w
i
th the sa
me s
i
ze
para
m
eter b
u
t
this featur
e is
app
arent
on
ly i
n
the
cas
e
of h
o
ri
z
o
nt
al orie
nt
ation.
T
h
e asy
m
metric
de
gre
e
of
forw
ard scatte
ring
an
d
back
scattering
incr
eases
w
hen
p
a
rticle s
i
z
e
inc
r
eases
w
hen
si
z
e
para
m
ete
r
of
particl
e is not e
xceed
ing
1.5.
Ke
y
w
ords
: as
pect ratio, orie
ntation, DDA, e
llips
o
i
d
particl
e
,
scattering pro
perties, 94 GH
z
Copy
right
©
2014 In
stitu
t
e o
f
Ad
van
ced
En
g
i
n
eerin
g and
Scien
ce. All
rig
h
t
s reser
ve
d
.
1.
Introducti
on
Cirru
s
cl
oud,
whi
c
h
regul
arly covers a
b
o
u
t
20%~30%
of the glo
be,
plays a
n
im
portant
role in the en
ergy bala
n
ce of the earth-a
tmosph
er
e sy
stem be
cau
s
e it reflects o
r
scatters sh
o
r
t
wave
radi
atio
n of the
sun,
but a
b
sorbin
g the l
ong
wave radiation
of the
atmo
sph
e
re
an
d t
he
earth'
s
surfa
c
e [1, 2], studying the radi
ation ch
ar
a
c
te
ri
stics of cirru
s
and
buildi
ng the datab
ase of
scattering p
r
o
pertie
s
are important [3].
Scatterin
g
an
d absorptio
n cha
r
a
c
teri
stics of ic
e pa
rticle
s in cirru
s
cloud
s rel
a
ted to its
sha
pe, di
men
s
ion,
ori
entati
on, compl
e
x refractive
ind
e
x
, incide
nt
wavelength
etc. Orie
ntation
of
particl
es, a
s
one of the mo
st importa
nt factors to
scat
tering comp
utation, has b
e
en discu
s
sed
[4
-
7].
Ping Yan
g
[
3
] studi
ed t
h
e opti
c
al
pro
pertie
s
of he
xagonal
ice
cry
s
tals with
differe
nt
asp
e
ct ratio
s
at rando
m ori
entation. Lei Che
ngxin
[4] studie
d
the influence of aspect ratio o
n
the
scattering p
r
opertie
s
of small size he
xagonal ic
e cry
s
tals in ci
rru
s cl
oud
s at 1.06um. Gong
Chu
n
wen [5]
studie
d
the in
fluence of a
s
pect
ratio
o
n
the
light-scattering prope
rties
of small si
ze
cylinder i
c
e particles in
cirrus
cl
oud
by T-matrix method. However,
t
hese literatures
mainly fo
cus
on visi
ble
an
d infrare
d
lig
hts; little literature
stu
d
ie
s
the influe
nce
of aspe
ct ratio an
d o
r
ie
nta
t
ion
on scatte
ring
prop
ertie
s
of i
c
e p
a
rti
c
les a
t
94
GHz, whi
c
h
h
a
s uniq
u
e
advanta
ge whe
n
dete
c
ti
ng
dynamic a
nd
stru
ctural ch
a
r
ac
teris
t
ics
of c
i
rrus
[6].
Becau
s
e the
r
e are ellip
soi
d
particl
e in cirru
s cl
oud, a
nd som
e
re
searche
r
s tho
ught it is
feasibl
e
to ca
lculate the
scattering p
r
op
erties of
i
c
e p
a
rticle
s at mil
limeter wavel
ength if we u
s
e
ellipsoid p
a
rti
c
le to
re
place
ice
crystal
s
with
ha
bits
of plate, colum
n
, and
nee
dl
e [8]. Thu
s
, this
pape
r u
s
e
s
DDA
method
to study th
e
influen
ce
of aspe
ct ratio
and
ori
entati
on on
scatte
ring
properties of
ellipsoid i
c
e
particl
e at 94 GHz, t
he result can provi
de
a re
ference for
retrieval
of
ice particles i
n
cirrus cloud.
Evaluation Warning : The document was created with Spire.PDF for Python.
ISSN: 23
02-4
046
TELKOM
NI
KA
Vol. 12, No. 11, Novem
ber 20
14: 75
43 – 754
8
7544
2. Introduce
of DDA Me
thod
The di
screte
dipole
app
roximation (DDA) i
s
a
ge
neral
metho
d
used to
compute
scattering
an
d ab
sorption
of electrom
agneti
c
wa
ve
s by pa
rticle
s of a
r
bitra
r
y geomet
ry a
nd
composition [9, 10]. Initially DDA
wa
s p
r
opo
se
d by P
u
rcell an
d Pe
nny pa
cker [9
], who repla
c
ed
the scatte
r b
y
a set of p
o
i
nt dipol
es.
Draine
an
d Fl
atau [11]
dev
elope
d the
DDA mo
del
an
d
provide
d
rele
vant code
s. T
he prin
cipl
e a
d
vantage of
DDA is that it
is flexible with rega
rd to the
geomet
ry of the target. In orde
r to obtai
n the des
i
r
ed
accura
cy the
inter-di
pole
spa
c
e mu
st b
e
sufficie
n
tly small when
co
mpared to
th
e wavelen
g
th
, this
req
u
ire
s
both l
a
rg
e
compute
r
me
mory
and lon
g
com
putation time whe
n
cal
c
ulat
e the large
r
p
a
rticle
s [12].
The ba
sic p
r
i
n
cipl
e of DDA
is as follo
ws
[6]:
Assuming the pol
ari
z
abilit
y is
j
and
the
dipol
e m
o
m
ent is
j
P
for the
j
th
dipol
e, the
DDA mo
del i
s
attempted t
o
find the sol
u
tion for
a se
lf-con
si
stent set of dipole
moment
s, wh
ich
can b
e
de
scri
bed with the f
o
llowin
g
form
ula:
,,
ex
t
j
in
c
j
j
jj
j
k
k
kj
PE
E
A
P
(1)
Whe
r
e
,
in
c
j
E
is the
electri
c
field
at the positio
n
j
due to the i
n
cid
ent plan
e
wave, and
jk
k
A
P
is
the contri
buti
on to the electri
c
field at the positio
n
j
due to the dipole at position
k
.
j
k
A
can be
expre
s
sed
by a fun
c
tion
of
angul
ar
wave
numb
e
r
K
and
the relative p
o
s
ition
of the
d
i
pole
s
j
and
k
. The
mathe
m
atical
expre
ssi
on
of
j
k
A
can
be fou
n
d
in
relevant lite
r
at
ure
[10][11].
Defining
1
jj
j
A
redu
ce
s the scatterin
g
prob
lem to find the dipole mo
m
ents
j
P
that satisfy a system
of
3N complex li
near e
quatio
n
s
:
,
1
N
inc
j
jk
k
k
AP
E
(2)
Whe
r
e
N i
s
th
e total n
u
mbe
r
of
dipole
s
.
Once
(2) ha
s
been
solved f
o
r the
un
kn
o
w
n
pola
r
izatio
ns
j
P
, the single
scatterin
g
pa
rameters in
clu
d
ing the
scat
tering a
nd a
b
so
rption
efficien
cie
s
, the
asymmet
r
y param
eter an
d
the phase matrix of scatte
ring may be e
v
aluated.
Figure 1. Gen
e
ral Pro
c
e
s
s of Computin
g
Scatteri
ng S
c
attering Effic
i
enc
y, Abs
o
rption Effic
i
ency,
As
ymmetr
y Fac
t
or
, Bac
kscatter
i
ng Cr
oss
Sec
t
ion and Phas
e Func
tion of Tar
g
et
Evaluation Warning : The document was created with Spire.PDF for Python.
TELKOM
NIKA
ISSN:
2302-4
046
The Influen
ce
of Aspect Ra
tio and Orie
ntation
to Scattering Prope
rti
e
s of… (Jinh
u
Wan
g
)
7545
Figure 1 sho
w
s
gen
eral
proce
s
s of com
puting
the
sin
g
le-scatterin
g
prop
ertie
s
of
studie
d
target. On
ce
the
code
s
o
f
ddscat.pa
r
file are
corre
c
tly set
acco
rding
to a
c
tu
al dem
and, t
he
singl
e-scattering pro
p
e
r
ties of target can
be get after cl
icki
ng dd
scat.exe.
3. The Influence of Aspect Ra
tio
and Orientation on
Scatteri
ng Properties of Ellipsoid Ice
Particles
Definition of aspect ratio of
ellip
soid ice particle
i
s
as follows:
b
a
(3)
Where b i
s
semi- minor axis of ellipsoi
d
, a is
the
semi-maj
or ax
is of
ellipsoid, which can
be
expre
s
sed a
s
Figure 2.
Figure 2. Ellipsoid Particle
The compl
e
x refra
c
tive index o
f
ellipsoid
ice pa
rti
c
le is
def
ined a
s
1.782
0.00270
mi
in thi
s
paper [13], the
effective radius
of com
puted ellipsoid i
c
e
particle
is defined as
follows:
1/
3
(3
/
4
)
eff
rV
(4)
The si
ze parameter of e
llipsoid i
c
e particle is:
2
ef
f
eff
r
xk
r
(5)
The
ellipsoid ice particl
e
can
be hori
zontal or
random ori
entation. If the elli
psoid is
hori
z
ontal
o
r
ientation,
the
prop
agatio
n dire
ction of
i
n
cid
ent el
ectromagn
etic
wave is pa
ralle
l to
the semi
-maj
or axis
of the ellipsoid a
nd the e
llip
soid ice
parti
cle can
rotate
about ho
ri
zo
ntal
plane, in ord
e
r to model
hori
z
ontal o
r
i
entation
in space, we averag
e the scattering p
r
op
erties
over about 100 ori
entatio
ns. If the ellipsoi
d
is random orientat
ion, the ellipsoi
d
ice particl
e
can
rotate a
bout
any direction;
we
avera
g
e
the sc
atteri
n
g
prope
rties
over 1
000
orientation
s
. T
he
scattering propertie
s
of absorptio
n
e
fficiency,
sca
ttering efficie
n
cy, asymm
e
try factor a
nd
backscatterin
g
efficien
cy with the aspe
ct
ratio varie
s
from 0.2 to 1.0 can b
e
sho
w
n in Figu
re
3,
4, 5, 6 resp
ectively.
If we multiply the absorp
t
ion efficien
cy,
the scattering efficie
n
cy and the backward
scattering
ef
ficien
cy with
the g
eom
e
t
ric
cro
s
s
-
s
e
ct
ion,
t
h
e
a
b
so
rpt
i
on
c
r
os
s-
se
ct
ion,
t
h
e
scattering
cro
s
s-sectio
n an
d the ba
ckwa
rd sca
tte
ring
cro
s
s-se
ction
can
be o
b
tai
ned, which are
freque
ntly used in the fiel
d of meteo
r
ol
ogy. The vert
ical coo
r
din
a
tes
of
Fi
gures
(2), (3), (4), (5
)
use th
e log
a
rithm of 10 in
a ba
se a
nd i
s
multiplie
d b
y
10 (
10
*
l
o
g
(
Q
or
)
abs
s
c
a
b
k
Qo
r
Q
) ,
the solid line
(left part)
sho
w
s the
scattering cha
r
a
c
te
ristic of the pa
rticle of
ho
rizontal orie
ntation
Evaluation Warning : The document was created with Spire.PDF for Python.
ISSN: 23
02-4
046
TELKOM
NI
KA
Vol. 12, No. 11, Novem
ber 20
14: 75
43 – 754
8
7546
and the
dotte
d line
(rig
h
t p
a
rt)
rep
r
e
s
ent
s the
scatte
ri
ng characte
ri
stic of the
pa
rticle
of ran
d
o
m
orientatio
n.
Figure 3. Absorption Efficiency of Ellipsoi
d
Part
icle
with Different Si
ze and Aspect Ratios
Figure 3(a), (b) show the variabl
e trend of absor
ption efficiency of t
he ellipsoid particles
at the horizon
tal orientation
and t
he ran
d
o
m orie
ntatio
n respe
c
tively.
Figure 3
(
a
)
shows th
at: (1
) when
the
si
ze
par
amete
r
is l
e
ss th
an
1.5, the
ab
sorption
efficien
cy of the pa
rticl
e
in
cre
a
ses with
the incre
a
si
n
g
of si
ze
pa
ra
meter, an
d
wi
th the same
size
para
m
eter
or
same vol
u
me
, the abso
r
pti
on efficien
cy
i
n
cr
ea
se
s if
t
he as
pe
ct
rat
i
o
incr
ea
se
s;
(2
)
whe
n
the si
ze
param
eter is
large
r
than 1.
5, the oscill
ating phe
nome
n
on hap
pen
s.
Figure 3
(
b)
shows the va
riable tre
nd
o
f
r
and
om o
r
i
entation, the
phen
omen
o
n
of the
absorption efficiency of
the particle increases with the increa
si
ng of
aspect ratio
will not happen
and the o
scill
ating phe
nom
enon al
so b
e
i
ng we
akene
d
compa
r
e
d
wi
th Figure 3
(
a
)
, which
can b
e
explained by
the effect of average.
Figure 4. Scattering Efficiency of Ellipsoi
d
Part
icle
with Different Si
ze and Aspect Ratios
Figure 4
(
a
)
, (b)
sh
ow the
variabl
e trend
of sca
tteri
ng
efficien
cy of t
he elli
psoid
p
a
rticle
s
at the horizon
tal orientation
or t
he ran
d
o
m
orientatio
n respe
c
tively.
Figure 4
(
a
)
shows th
at: (1
)
when
the
size
paramete
r
i
s
le
ss tha
n
1.5, the
sca
ttering
efficien
cy of the pa
rticl
e
in
cre
a
ses with
the incre
a
si
n
g
of si
ze
pa
ra
meter, an
d
wi
th the same
size
para
m
et
er o
r
same v
o
lu
me
,
t
he scat
t
e
rin
g
ef
f
i
cien
cy
incr
ea
se
s if
t
he asp
e
ct
rat
i
o
incre
a
s
e
s;
(
2
)
whe
n
the
si
ze pa
ram
e
ter i
s
la
rge
r
th
an
1.5, the o
s
cill
ating p
heno
m
enon
hap
pen
s
whi
c
h m
e
a
n
s
that the relat
i
onship b
e
tween
scatterin
g
efficien
cy
and
size p
a
rameter or orientation i
s
n
o
t
obviou
s
.
Figure 4
(
b)
shows the va
riable tre
nd
o
f
r
and
om o
r
i
entation, the
phen
omen
o
n
of the
scattering
efficiency of the parti
cl
e increases with the increasi
ng
of
aspect ratio
will not happen
and th
e o
s
cil
l
ating p
heno
menon
al
so
being
wea
k
e
ned
com
p
a
r
e
d
with
Figu
re
4(a
)
due
to
the
effect of average.
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TELKOM
NIKA
ISSN:
2302-4
046
The Influen
ce
of Aspect Ra
tio and Orie
ntation
to Scattering Prope
rti
e
s of… (Jinh
u
Wan
g
)
7547
Besides that, com
pared t
o
Figu
re
3, the scatteri
ng effici
ency
of the ellipsoidal i
c
e
particl
es i
s
much la
rg
er
than the ab
sorption
effici
ency be
ca
use imagina
ry part of com
p
lex
refrac
tive index of ic
e is
small at 94GHz frequ
en
cy.
Figure 5. Asymmetry Para
meter of Ellipsoid Pa
rt
icle
with Differe
nt Size and A
s
p
e
ct Ratio
s
Figure 5(a
)
, (b) sh
ow the
cha
nge tre
n
d
of asy
mmetry factor of the ellipsoi
d
pa
rticle
s a
t
the hori
z
ontal
orientation o
r
the
rando
m orientatio
n re
spe
c
tively.
Figure 5(a)
shows that: (1
) wh
en the
si
ze p
a
ra
meter is le
ss tha
n
1.5, the asy
mmetry
factor
of the
particl
e in
cre
a
se
s
with th
e increa
se
of size pa
ram
e
ter, and
with
the sam
e
si
ze
para
m
eter
or
same vol
u
me
, asymmetry factor
g in
cr
eas
es
if th
e
a
s
pe
c
t
r
a
tio
in
cr
ea
s
e
s
;
(
2
)
wh
en
the size para
m
eter is la
rge
r
than
1.5, the oscillating p
henom
eno
n h
appe
ns.
Figure 5
(
b)
shows the va
riable tre
nd
o
f
r
and
om o
r
i
entation, the
phen
omen
o
n
of the
asymmet
r
y factor of the pa
rticle in
crea
ses with
the in
cre
a
si
ng of a
s
pe
ct ratio wil
l
not happen
and
the oscillating
phenom
eno
n
also bei
ng weakene
d com
pare
d
with Fi
gure 5
(
a
)
.
Acco
rdi
ng to
Figure 5, the
scatter
can
b
e
re
garded
a
s
Rayleigh
scattering
wh
en
parti
cle
is
smalle
r th
an in
cide
nt
wavele
ngth
whi
c
h m
ean
s asymm
e
try i
s
small. As the pa
rticl
e
’s
size
become
s
la
rg
er, the e
n
e
r
g
y
of incide
nt
electroma
g
n
e
tic
w
a
ve is
ab
s
o
r
b
ed
w
h
en
it is
r
e
fr
ac
te
d
into the inte
ri
or of the
part
i
cle, the m
a
in
ene
rg
y source of
scatteri
ng c
haracte
ri
stic com
e
s
from
diffraction, which
l
ead
s
to forwa
r
d scattering
i
s
la
rge
r
than b
a
ckward
scatterin
g
and the
deg
ree
of asymmetry
becom
es la
rger.
Figure 6. Backscatte
ring Efficien
cy of Ellipsoi
d
Particl
e
with Different
Size and Aspect Ratios
Figure 6
(
a
)
,
(b) sho
w
the
variabl
e tre
nd of th
e dif
f
erential
ba
ckscatte
ring
e
fficiency
(
b
ac
ksc
atter
i
ng effic
i
enc
y
is
the differ
ential bac
kscatter
i
ng effic
i
enc
y multiplied by
4
) of the
ellipsoidal particles at the horizontal orient
ation or the
random ori
e
ntation respectively.
Figure 6(a)
sho
w
s that: (1)
Wh
en
the si
ze p
a
rameter i
s
le
ss th
an a
b
o
u
t 1.5,
backscatterin
g
efficiency i
n
crea
se
s wit
h
the incre
a
se of size pa
ra
meter, and wi
th the same size
para
m
eter o
r
same volum
e
, Backscattering efficie
n
cy increa
se
s if the aspe
ct
ratio increa
se
s;
(2)
Whe
n
the size paramet
er is lag
e
r
tha
n
about 1.5, the oscillation
occurs.
Figure 6
(
b)
shows the va
riable tre
nd
o
f
r
and
om o
r
i
entation, the
phen
omen
o
n
of the
backscatterin
g
efficien
cy of the particl
e increa
se
s with the increasi
ng of aspect ratio will
not
happ
en an
d the oscillating
phen
omen
on
also b
e
ing
we
ake
ned
comp
ared
with Fig
u
re 6
(
a).
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ISSN: 23
02-4
046
TELKOM
NI
KA
Vol. 12, No. 11, Novem
ber 20
14: 75
43 – 754
8
7548
4. Conclusi
on
The p
ape
r a
nalyse
s
the
i
n
fluen
ce of t
he pa
rticl
e
size p
a
ramete
r, aspe
ct rati
o and
orientatio
n o
n
scatteri
ng
prop
ertie
s
u
s
ing the
discrete dipol
e Ap
proximatio
n (DDA
) meth
o
d
at
94G
Hz fre
q
u
ency. T
he
re
sult
sho
w
s th
at: whe
n
the
size p
a
ra
met
e
r
of ice p
a
rti
c
le i
s
l
e
ss th
an a
limit value (typical value 1.
5) in this paper, t
he scattering properties of t
he ellipsoid ice particl
e
s
increa
se
with
the in
cre
a
si
ng of the
si
ze pa
ramete
r wheth
e
r at
h
o
rizontal
orie
ntation o
r
at
the
rand
om o
r
ien
t
ation, and
wi
th the sa
me
size p
a
ra
mete
r or
sa
me vol
u
me, the valu
es of
scatteri
ng
prop
ertie
s
in
crea
se if the a
s
pe
ct ratio i
n
cre
a
se
s
exce
pt asymmetry
factor.
When
size pa
ramet
e
r
excee
d
s
a li
mit value (1.5), o
scill
ation
phen
ome
n
o
n
o
c
curs. Th
e scatteri
ng
efficien
cy is
much
large
r
than th
e absorptio
n efficien
cy; the rea
s
on i
s
that the imagi
nary pa
rt of complex refractive
index of ice i
s
sm
all (
0.0027
i
) at 94GHz freq
uen
cy. Ellipsoid ice
parti
cle’s forwa
r
d
and
backward
scattering
asym
metry incre
a
ses
with the i
n
cre
a
si
ng of
si
ze p
a
ramete
r until it rea
c
h
e
s
the limit value. This p
ape
r establi
s
h
ed
a datab
as
e b
e
twee
n the
scatterin
g
cha
r
acteri
stic
and
the
ellipsoid pa
rticle
s and p
r
ov
iding a refe
re
nce for
millim
eter-wave ra
dar to dete
c
t the ellipsoid ice
particl
es.
Ackn
o
w
l
e
dg
ements
Than
ks to Professor B.T. Drai
ne
of Pri
n
ceto
n Unive
r
sity for
providing u
s
with t
he DDA
pro
c
ed
ures.
This
re
sea
r
ch wa
s
sup
p
o
r
ted by Th
e
Nation
al Spe
c
ial
Re
sea
r
ch Fund fo
r
Non-
Profit Section (meteo
rolo
gical
)
: Re
sea
r
ch o
n
the key technolo
g
y
of millimeter Clo
ud Ra
dar.
(Grant No.
GYHY20
120
6038
) and
suppo
rted by
Grad
uate
Students’ Scientific Re
se
arch
Innovation
Program of
Jiang
su
High
er Edu
c
ation In
stitution of China (G
ra
nt No.
CXLX12
_05
0
0
)an
d
supp
o
r
ted by Nati
onal Nature
Scien
c
e Fo
u
ndation of
China: Study on
electroma
gne
tic glint supp
ressio
n and
microphy
sica
l
inversio
n of clou
d usin
g millimeter wa
ve
MIMO rad
a
r(Grant
No. 61
3720
66)
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