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2
3
Definition 1.
We say that a pair of vector-valued functions
Hx Hx
(), ()
∈
L R C
( ,
v
)
are biorthogonal, if their translations satisfy
3
[( , (
HH n
⋅
⋅−=
]
δ
I
,
nZ
∈
,
(2)
0
,
nv
I
denotes the
vv
×
δ
where
is the Kronecker symbol.
Definition 2.
A sequence of vector-valued functions
indentity matrix and
0
,
n
2
3
v
is
{( }
Hx
∈
⊂⊂
U LRC
(,
)
n
3
nZ
called a Riesz basis of
U
if itsatisfies
(i)
for any
Gx
()
∈
U
, there exists a unique
2
3
vv
×
vv
×
{}
Q
∈
∈
ℓ
( )
Z
matrix sequence
such that
n
s
nZ
∑
3
Gx
()
=
QH x
(),
x R
∈
,
(3)
nn
3
nZ
∈
1
v
∑∑
2
3
vv
×
3
uu
×
2
ℓ
()
Z
=
{:
Q
Z
→ =
C
,
Q
|
qn
( ) | )
<+∞
,
where
2
(ii)
there
ls
,
2
4
ls
,
= ∈
1
nZ
0
<≤<+∞
CC
{}
n
M
exist two constants
such that, for any matrix sequence
,
1
2
3
nZ
∈
the following equality follows.i.e.,
∑
CM
{}||
≤
MHx C M
( ||
≤
{},
(4)
1
n
n
n
2
n
*
*
3
nZ
∈
In what follows, we introduce the notion of vector- valued multiresolution analysis
and give the definition of biorthogonal vector-valued wavelets of space
v
LR C
.
2
3
(,
)
Definition 3.
A vector-valued multiresolution analysis of the space
v
LR C
is a
2
3
(,
)
ℓ
nested sequence of closed subspaces
{}
Z
Y
YY
⊂∀∈
1
,
Z
;
such that (i)
(ii)
ℓℓ
∈
ℓ
ℓ
∩
ℓ
∪
ℓ
Y
=
{0}
Z
Y
and
is dense in
v
LR C
, where 0 denotes an zero vector of
2
3
(,
)
∈
Z
ℓ
∈
ℓ
v
ℓ
R
;
Φ∈⇔Φ
ℓ
(
xY
(
Mx
)
∈∀∈
Y
,
Z
space
(iii)
; (iv) there exists
ℓ
1
Fx
()
∈
Y
,called a vector-valued scaling function, such that its translates
0
3
nZ
n
Fx
():
=−
Fx n
(
),
∈
Y
0
.
forms a Riesz basis of subspace
Fx
()
∈⊂
Y
Y
, by Definition 3 and (4) there exists a finitely supported se-
quence of constant
vv
Since
0
1
×
matrice
such that
{}
Ω
ℓ
2
(
Z
3
vv
×
n
3
nZ
∑
(5)
Fx
()
∈
=Ω
FMx n
(
−
).
n
3
nZ
Equation (6) is called a refinement equation. Define
∑
3
⋅
()
γ
=
⋅
exp{
− ⋅
in
γ
},
γ
∈
R
.
m
Ω
Ω
(6)
n
3
nZ
∈
s
, which is
2
π
Z
Fx
. Thus, (6) becomes
3
()
where ( )
Ω
γ
fun., is called a symbol of
ˆ
ˆ
FM
(
γ
)
=Ω
() (),
γ
F
γ
γ
∈
R
. (7)
Xj Z
∈
Y
in
Y
+
1
.
Let
be the direct complementary subspace of
Assume that
,
ψ
()
xLRC
∈
23
( ,
v
),
μ
∈Γ
there exist 63 vector-valued functions
such that their
μ
X
tran- slations and dilations form a Riesz basis of
i.e.,
j
,
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