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    Poularikas A. D. The Mellin Transform

    The Handbook of Formulas and Tables for Signal Processing.Ed. Alexander D. Poularikas

    Boca Raton: CRC Press LLC,1999

    1999 by CRC Press LLC

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    1999 by CRC Press LLC

    18The Mellin Transform18.1 The Mellin Transform

    18.2 Properties of Mellin Transform

    18.3 Examples of Mellin Transform

    18.4 Special Functions Frequency Occuring in Mellin Transforms

    18.5 Tables of Mellin Transform

    References

    18.1 The Mellin Transform

    18.1.1 Definition

    Example

    18.1.2 Relation to Laplace Transform

    By letting the transform becomes

    18.1.3 Relation to Fourier Transform

    By setting in 18.1.2 we obtain

    which implies that

    M{ ( ); } ( ) ( )f t s F s f t t dts= =

    01

    M{ ( )} ( )e u t e t dt a sat at s s

    = =01

    t e dt e dxx x= = , ,

    M{ ( )} ( ) ( ) { ( )}f t F s f e e dx f ex sx x= = =

    L

    s j= + 2

    F s f e e e dxx axj x( ) ( )=

    2

    M{ ( ); } { ( ) ; }f t s j f e ex ax= + = 2 F

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    where

    Fourier Transform

    18.1.4 Inversion Formula

    where c is within the strip of analyticity

    18.2 Properties of Mellin Transform

    18.2.1 Scaling Property

    18.2.2 Multiplication by ta

    18.2.3 Raising the Independent Variable to a Real Power

    18.2.4 Inverse of Independent Variable

    18.2.5 Multiplication by ln t

    18.2.6 Multiplication by a Power of ln t

    F{ ( ); } ( )f x f x e dxj x = =

    2

    f tj

    F s t ds

    c j

    c j

    s( ) ( )=

    +

    12a s b<

    0

    1

    0

    1 11 11

    0

    M{ ( ); } ( )t f t s F s = 1 1 1

    M{ln ( ); } ( )t f t sd

    dsF s=

    M{(ln ) ( ); } ( )t f t sd

    dsF sk

    k

    k=

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    18.2.7 Derivat ive

    18.2.8 Derivative Multiplied by Independent Variable

    Example

    18.2.9 Convolut ion

    18.2.10 Multiplicative Convolution

    Properties of the Multiplicative Convolution

    1. commutative

    2. associative

    3. unit element

    4.

    5.

    6.

    Md

    dsf t s s k F s k

    k

    k

    k

    k( ); ( ) ( ) ( )

    = 1

    ( ) ( )( ) ( )( )!

    ( )!

    ( )

    ( )s k s k s k s

    s

    s k

    s

    s kk

    + =

    =

    1 1

    1

    1L

    M td

    dsf t s s F s

    s k

    sF s s s s s k k

    k

    k

    k

    k

    k

    k( ); ( ) ( ) ( ) ( )

    ( )

    ( )( ), ( ) ( ) ( )

    = = + = + + 1 1 1 1

    L

    M td f t

    dtt

    df t

    dts s F s

    22

    2

    2( ) ( ) ; ( )+

    =

    M{ ( ) ( ); } ( ) ( )f t g t sj

    F z G s z dz

    c j

    c j

    =

    +

    12

    M M

    M

    { } ( ) ; ( ) ( )

    { ( ) ( )} ( )

    f g ft

    ug u

    du

    us F s G s

    F s G s f t

    ug u

    du

    u

    =

    =

    =

    0

    1

    0

    0

    f tu g udu

    u( )

    f g g f =

    ( ) ( )f g h f g h =

    f t f =( )1

    td

    dtf g t

    d

    dtf g f t

    d

    dtg

    k k k

    =

    =

    ( )

    (ln )( ) [(ln ) ] [(ln ) ]t f g t f g f t g = + ( ) ( )t a f a f a t = 1 1

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    18.2.11 Parsevals Formulas

    where

    18.3 Examples of Mellin Transform

    18.3.1 Example

    18.3.2 Example

    .

    Setting we obtain: Hence ,

    18.3.3 Example

    From with the setting we obtain

    .

    Hence,

    .

    18.3.4 Example

    Using 18.2.3 and 18.3.3 we obtain

    ( ) ( ) ( ), ,

    ( )( )

    t p t p t pp p p

    d t

    dtf

    d

    dst f

    k

    k

    k

    k

    = >

    =

    0

    1

    0

    0

    2 1

    1

    21

    +

    +

    =

    =

    f t g tj

    f s g s ds

    f t g t t dt f g d

    c j

    c j

    r

    ( ) ( ) { ; } { ; }

    ( ) ( ) { }( ) { }( )

    M M

    M M

    M{ }( ) ( )f f t t dt

    j r

    =

    +

    02

    M{ ( )} , Re{ }t u t t t dt t

    a ss aa

    t

    a s o

    a s

    = = +

    <

    + +

    0 10

    M1

    1

    1

    10

    1

    +

    =+

    t s tt dts;

    tx

    + =

    11

    1x

    t

    tdx

    dt

    t=

    +=

    +1 1 2,

    ( ).

    M f s xx

    x

    dx

    xx x dx B s s s s

    s

    s

    s

    s

    s s; ( )( ) ( )

    ( ) ( , ) ( ) ( )sin

    Re{ } .

    { } =

    = = = =

    < > ( )

    ( ) ( )

    ( ), Re{ } , Re{ } ,

    u x x= +/( ),1

    0

    1

    1

    + + = +x

    xdx

    m s

    m s

    s

    m s( )

    ( ) ( )

    ( )

    M{( ) ; }( ) ( )

    ( ), Re{ } Re{ }1 0+ =

    <

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    .

    18.3.5 Example

    (see 5.3.1)

    18.3.6 Example

    From 18.3.1 and 18.3.5 and hence,

    18.4 Special Functions Frequency Occurring in Mellin

    Transforms

    18.4.1 Definition

    The gamma function (s) is defined on the complex half-plane Re(s) > 0 by the integral

    18.4.2 Analytic Continuation

    The analytical continued gamma function is holomorphic in the whole plane except at the points s =

    where it has a simple pole.

    18.4.3 Residues at the Poles

    18.4.4 Relation to the Factorial

    18.4.5 Functional Relations

    M{( ) ; }

    ( / )

    ( ), Re{ } Re{ }1 0+ =

    <

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    (Legendres duplication formula)

    (Gauss-Legendres multiplication formula)

    (Stirling asymptotic formula)

    18.4.6 The Beta Function

    Definition:

    Relation to the gamma function:

    18.4.7 The psi Function (logarithmic derivative of the gamma function)

    Definition:

    Eulers constant , also called C, is defined by

    and has value ....

    18.4.8 Riemanns Zeta Function

    The function (z) is analytic in the whole complex z-plane except inz = 1 where it has a simple pole

    with residue equal to +1.

    1

    2

    =

    ( ) ( ) ( / )/2 2 1 21 2 2 1s s ss= +

    ( ) ( ) ( / ), , , ,/ ( ) /ms m s k m mms m

    k

    m

    = + =

    =

    1 2 1 20

    1

    2 2 3 L

    ( ) ~ exp ( ) , , arg( )/s s ss

    O s s ss2 11

    12

    1 2 2 +

    +

    >

    =

    =

    0

    0

    11 0 1 2

    11

    L

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    18.5 Tables of Mellin Transform

    18.5.1 Tables of Mellin Transform

    TABLE 18.1 Some Standard Mellin Transform Pairs

    Original Function Mellin Transform

    Strip of holomor phy

    Algebraic Functions

    Exponential Functions

    f t t( ), > 0 M f s f t t dts[ ; ] ( )

    10

    u t a t ab( ) , > 0 +

    +a

    b s

    b s

    Re( ) Re( )s b<

    ( ( ) ( ))u t a u t t b +

    +a

    b s

    b s

    Re( ) Re( )s b>

    ( )1 1+ t sin( )s

    0 1<

    t t

    t

    h

    h

    h

    s

    h

    sh

    +

    1

    ( )

    Re( )s > 0

    ( )( )1 1 1 t ta na na n

    s

    na

    s a

    nasin csc csc

    +

    0 1< < Re( ) ( )s n a

    e ppt >, 0 p ss ( ) Re( )s > 0

    ( )e t 1 1 ( ) ( )s s Re( )s > 1

    ( ( ) s = zeta function)

    ( ) , Re( )e aat + >1 01 a s ss s ( )( ) ( )1 21 Re( )s > 0

    ( ) , Re( )e a

    at

    >

    1 0

    1

    a s s

    s

    ( ) ( ) Re( )s > 1( )( ) , Re( )e e aat t >1 01 ( ) ( , )s s a Re( )s > 1

    ( )et 1 2 ( )[ ( ) ( )]s s s 1 Re( )s > 2

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    Logarithmic Functions

    Trigonometric Functions

    TABLE 18.1 Some Standard Mellin Transform Pairs (continued)

    Original Function Mellin Transform

    Strip of holomor phyf t t( ), > 0 M f s f t t dt s[ ; ] ( )

    1

    0

    e a hath > >, Re( ) ,0 0 h a s hs h 1 / ( / ) Re( )s > 0

    t e t 1 1 ( )1 s < >e a hath

    , Re( ) , h a s hs h1 / ( / ) < 0p

    s

    s

    2Re( )s > 0

    sin( ),at a > 0 a s ss ( )sin( / ) 2 < sin( ), Re( ) Im ( ) ( )sin tan/a s sa

    s2 2 2 1+

    Re( )s > 1

    sin ( ),2 0at a > 2 21s sa s s( )cos( / ) < 0 a s ss ( )cos( / ) 2 0 1<

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    References

    Bertrand, Jacqueline, Pierre Bertrand, and Jean-Philippe Ovarlez, The Mellin Transform, in Transforms

    and Applications Handbook, ed. Alexander Poularikas, CRC Press, Boca Raton, Florida, 1996.

    Davies, G.,Integral Transforms and Their Applications, 2nd ed., Springer-Verlag, New York, NY, 1984.

    Erdelyi, A., W. Magnus, F. Oberhettinger, and F. G. Tricomi, Tables of Integral Transfer, McGraw-Hill

    Book Co., New York, NY, 1954.

    Oberhettinger, F., Tables of Mellin Transform, 2nd ed., Springer-Verlag, New York, NY, 1974.

    Sneddon, Ian N., The Use of Integral Transform, McGraw-Hill Book Co., New York, NY, 1972.

    Other Functions

    whole plane

    none (analytic functional)

    TABLE 18.1 Some Standard Mellin Transform Pairs (continued)

    Original Function Mellin Transform

    Strip of holomor phyf t t( ), > 0 M f s f t t dt s[ ; ] ( )

    1

    0

    J at a ( ), > 02

    2 2

    2 21

    1s

    s

    s

    as

    +

    +

    < 02

    1

    2

    1

    2 2 2

    1 12 2

    1v

    s

    ss

    a v ss

    + +

    +

    ( )

    < < 0 ps1

    ( ),t pn pn

    >=

    01

    p ss 1 1( ) Re( )s < 0

    J t ( )2 2

    1 2 1

    1s s

    s

    + +

    ( ) /

    [( / )( ) ]

    < =0, real = Im( )s

    tb ( )b s+

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