MATLAB Answers

Noel

I need to find difference equation and frequency response

Asked by Noel
on 15 Nov 2011

Given H(z)=(-3+z^z-1)/(1+2z^-1+3z^-2)

a) Find the difference equation

b) Plot the frequency response

  1 Comment

Naz
on 15 Nov 2011

Right. And what's your question?

Tags

Products

No products are associated with this question.

2 Answers

Answer by Walter Roberson
on 15 Nov 2011

Please see this previous discussion

However, it appears to me that your equation probably cannot be analyzed through these techniques, as it is not in the form of a ratio of polynomials. The z^z term is going to lead you to a lot of problems.

  0 Comments


Answer by Naz
on 15 Nov 2011

Difference equation (I assume that z^z-1 should be z^-1):

3y[n-2]+2y[n-1]+y[n]=-3x[n]+z[n-1]

Frequency response:

B=[-3 1];
A=[1 2 3];
[H,W] = freqz(B,A);
plot(W,H);

  2 Comments

Naz
on 15 Nov 2011

The frequency is normalized to pi

Walter Roberson
on 15 Nov 2011

My speculation was that the z^z-1 should be z^2 - 1 but that doesn't make sense with the leading -3 . So I still don't know what was intended.


Discover what MATLAB® can do for your career.

Opportunities for recent engineering grads.

Apply today