Problem Set 3. Q3

Re: Problem Set 3. Q3

by Tim Tuuva -
Number of replies: 0
Hello,


The following figure shows the spectrum of   |X(\omega)|  and  |H(\omega)| .

Spectrum of H and X


Let us observe for example  |H(\omega)| , you see that it is zero for frequencies below  -\frac{\pi}{5} or above  \frac{\pi}{5} .
This is called an ideal low pass filter.

Its cut-off frequency is  \omega_c =  \frac{\pi}{5} here. Everything is set to zero above this cut-off frequency.
Note if you filter a signal x(t) with h(t). It ends up multiplying in the Fourier domain, hence we get the final answer.


Let me know if it is still unclear