Signum function and Fourier transform












0














I'm extracting a portion of my notes which I believe I might have copied wrongly.



Given this equation:



$$frac{G(omega)}{2icomega} [e^{icomega t}-e^{-icwt}]$$



I want to find the Fouerir transform of the above. I believe it involves the Fourier transform of the signum function.
The Signum function is:



$$sgn(x) = left{begin{matrix}
1 ,&x>0 \
0,&x=0 \
-1, &x<0
end{matrix}right.$$
On my notes it says the Fourier transform of sgn(x) to be
$$frac{1}{pi iomega}$$ (is this the correct?)



Secondly, how do I apply the fourier transform to the above equation?



I'm pretty lost so any help would be good.










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  • What is $G$? The formula works out to $G(omega)frac{sin(comega t)}{comega}$, with no signum directly in sight.
    – Henning Makholm
    Jun 15 '15 at 10:57










  • G is the fourier transform of some g(x), both of which has not yet been defined.
    – Mathematicing
    Jun 15 '15 at 10:58


















0














I'm extracting a portion of my notes which I believe I might have copied wrongly.



Given this equation:



$$frac{G(omega)}{2icomega} [e^{icomega t}-e^{-icwt}]$$



I want to find the Fouerir transform of the above. I believe it involves the Fourier transform of the signum function.
The Signum function is:



$$sgn(x) = left{begin{matrix}
1 ,&x>0 \
0,&x=0 \
-1, &x<0
end{matrix}right.$$
On my notes it says the Fourier transform of sgn(x) to be
$$frac{1}{pi iomega}$$ (is this the correct?)



Secondly, how do I apply the fourier transform to the above equation?



I'm pretty lost so any help would be good.










share|cite|improve this question






















  • What is $G$? The formula works out to $G(omega)frac{sin(comega t)}{comega}$, with no signum directly in sight.
    – Henning Makholm
    Jun 15 '15 at 10:57










  • G is the fourier transform of some g(x), both of which has not yet been defined.
    – Mathematicing
    Jun 15 '15 at 10:58
















0












0








0







I'm extracting a portion of my notes which I believe I might have copied wrongly.



Given this equation:



$$frac{G(omega)}{2icomega} [e^{icomega t}-e^{-icwt}]$$



I want to find the Fouerir transform of the above. I believe it involves the Fourier transform of the signum function.
The Signum function is:



$$sgn(x) = left{begin{matrix}
1 ,&x>0 \
0,&x=0 \
-1, &x<0
end{matrix}right.$$
On my notes it says the Fourier transform of sgn(x) to be
$$frac{1}{pi iomega}$$ (is this the correct?)



Secondly, how do I apply the fourier transform to the above equation?



I'm pretty lost so any help would be good.










share|cite|improve this question













I'm extracting a portion of my notes which I believe I might have copied wrongly.



Given this equation:



$$frac{G(omega)}{2icomega} [e^{icomega t}-e^{-icwt}]$$



I want to find the Fouerir transform of the above. I believe it involves the Fourier transform of the signum function.
The Signum function is:



$$sgn(x) = left{begin{matrix}
1 ,&x>0 \
0,&x=0 \
-1, &x<0
end{matrix}right.$$
On my notes it says the Fourier transform of sgn(x) to be
$$frac{1}{pi iomega}$$ (is this the correct?)



Secondly, how do I apply the fourier transform to the above equation?



I'm pretty lost so any help would be good.







pde fourier-analysis fourier-series






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asked Jun 15 '15 at 10:54









Mathematicing

2,44121851




2,44121851












  • What is $G$? The formula works out to $G(omega)frac{sin(comega t)}{comega}$, with no signum directly in sight.
    – Henning Makholm
    Jun 15 '15 at 10:57










  • G is the fourier transform of some g(x), both of which has not yet been defined.
    – Mathematicing
    Jun 15 '15 at 10:58




















  • What is $G$? The formula works out to $G(omega)frac{sin(comega t)}{comega}$, with no signum directly in sight.
    – Henning Makholm
    Jun 15 '15 at 10:57










  • G is the fourier transform of some g(x), both of which has not yet been defined.
    – Mathematicing
    Jun 15 '15 at 10:58


















What is $G$? The formula works out to $G(omega)frac{sin(comega t)}{comega}$, with no signum directly in sight.
– Henning Makholm
Jun 15 '15 at 10:57




What is $G$? The formula works out to $G(omega)frac{sin(comega t)}{comega}$, with no signum directly in sight.
– Henning Makholm
Jun 15 '15 at 10:57












G is the fourier transform of some g(x), both of which has not yet been defined.
– Mathematicing
Jun 15 '15 at 10:58






G is the fourier transform of some g(x), both of which has not yet been defined.
– Mathematicing
Jun 15 '15 at 10:58












1 Answer
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$$x(t) = sgn(t)$$



$$frac{dx(t)}{dt} = 2delta(t)$$



Now take fourier transform in both side



$$(jomega)X(omega) = 2$$



$$ X(omega) = frac{2}{jomega}$$



$$sgn(t) rightleftharpoons frac{2}{jomega}$$






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    1 Answer
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    1 Answer
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    0














    $$x(t) = sgn(t)$$



    $$frac{dx(t)}{dt} = 2delta(t)$$



    Now take fourier transform in both side



    $$(jomega)X(omega) = 2$$



    $$ X(omega) = frac{2}{jomega}$$



    $$sgn(t) rightleftharpoons frac{2}{jomega}$$






    share|cite|improve this answer


























      0














      $$x(t) = sgn(t)$$



      $$frac{dx(t)}{dt} = 2delta(t)$$



      Now take fourier transform in both side



      $$(jomega)X(omega) = 2$$



      $$ X(omega) = frac{2}{jomega}$$



      $$sgn(t) rightleftharpoons frac{2}{jomega}$$






      share|cite|improve this answer
























        0












        0








        0






        $$x(t) = sgn(t)$$



        $$frac{dx(t)}{dt} = 2delta(t)$$



        Now take fourier transform in both side



        $$(jomega)X(omega) = 2$$



        $$ X(omega) = frac{2}{jomega}$$



        $$sgn(t) rightleftharpoons frac{2}{jomega}$$






        share|cite|improve this answer












        $$x(t) = sgn(t)$$



        $$frac{dx(t)}{dt} = 2delta(t)$$



        Now take fourier transform in both side



        $$(jomega)X(omega) = 2$$



        $$ X(omega) = frac{2}{jomega}$$



        $$sgn(t) rightleftharpoons frac{2}{jomega}$$







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Mar 27 at 8:23









        Ashok Saini

        1215




        1215






























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