- #1
Lightning19
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Homework Statement
A linear time-invariant filter is described by the difference equation
y[n] = x[n] - x[n-2]
a) Obtain an expresson for the frequency response of this system.
b) Sketch the frequency response (magnitude and angle) as a function of frequency.
2. The attempt at a solution
a) {bk} = {1, 0, -1}
H(e^-jw)= 1-e^-j2w
b) I am not sure how to plot the magnitude.
H(e^-jw)= 1-e^-j2w = (e^-jw)(2*j*sin(w))
where (e^-jw) is the angle and (2*j*sin(w)) is the magnitude.
However, there is an imaginary number, j, in the magnitude...what do I do with this?
Thank you.