Signal Processing Asked by John_HB on November 13, 2021
The signal $x(t)=e^{-t^2}text{sinc}(t)$ was sampled at interval $T$. It was then found that the discrete time Fourier transform of the sampled signal is: $X(e^{jomega})=1$. What is the minimum $T$ for which such a result is possible? If this is impossible for any $T$, explain why.
I started it but didn’t how to continue , any help? My steps so far:
begin{align}
x[n] &= e^{-n^2}text{sinc}[n] \
&= e^{-n^2}frac{text{sin}(pi n)}{pi n} \
&= frac{e^{-n^2}}{2j pi n}big(e^{jpi n} – e^{-jpi n}big) \
&= frac{1}{2j pi n}big( e^{jpi n – n^2} – e^{-jpi n – n^2} big) \
end{align}
begin{align}
X(e^{jomega}) &= 1 \
&= sum_{n=0}^{infty} x[n]e^{-jomega n} \
&= sum_{n=0}^{infty} frac{1}{j2pi n} big( e^{jpi n – n^2} – e^{-jpi n – n^2} big)
end{align}
The best answer I could give is just a hint: think about what is the inverse discrete time Fourier transform of $X(e^{jomega})$. Constants in the frequency domain are what in the time domain? Answering that will lead you to the answer of this question.
Answered by Engineer on November 13, 2021
Get help from others!
Recent Questions
Recent Answers
© 2024 TransWikia.com. All rights reserved. Sites we Love: PCI Database, UKBizDB, Menu Kuliner, Sharing RPP