I have to use Fourier Transform without frequency range?

I have to use Fourier Transform without frequency range?

Answer 1

[Star Strider]

One approach —

A = [1 0.43 0.95];
B = [0.97 0.43 0.97];

[h,t] = impz(B,A);

figure
subplot(2,1,1)
plot(t, h)
grid
subplot(2,1,2)
plot(t,h)
grid
axis([0  100    [-1 1]*0.1])

Experiment to get different results, and consider using the Control System Toolbox functions as well.

H = tf(B,A)

H =
 
  0.97 s^2 + 0.43 s + 0.97
  ------------------------
    s^2 + 0.43 s + 0.95
 
Continuous-time transfer function.

figure
impulse(H)

It would of course help to know the sampling frequency.

.

[Star Strider]

The Fourier transform requirement was not part of — and not mentioned in — the original question. It was originally about finding the impulse response of the IIR filter described by ‘A’ and ‘B’.

I am not certain what ‘Fourier Transform without frequency range’ means in this context. If further information exists to expand on that, I will do my best to at least outline the approach.

.