Butterworth impulse response

1. What is impulse response of Butterworth filter?
2. Is Butterworth a FIR or IIR?
3. Why Chebyshev is better than Butterworth?
4. Why is Butterworth filter better?

What is impulse response of Butterworth filter?

The frequency response of the Butterworth filter is maximally flat (i.e. has no ripples) in the passband and rolls off towards zero in the stopband. When viewed on a logarithmic Bode plot, the response slopes off linearly towards negative infinity.

Is Butterworth a FIR or IIR?

The classical IIR filters, Butterworth, Chebyshev Types I and II, elliptic, and Bessel, all approximate the ideal “brick wall” filter in different ways.

Why Chebyshev is better than Butterworth?

Chebyshev type I filter minimizes the height of the maximum ripple. For the same filter order, the stopband attenuation is higher for the Chebyshev filter. Compared to a Butterworth filter, a Chebyshev-I filter can achieve a sharper transition between the passband and the stopband with a lower order filter.

Why is Butterworth filter better?

Butterworth filters are used in control systems because they do not have peaking. The requirement to eliminate all peaking from a filter is conservative. Allowing some peaking may be beneficial because it allows equivalent attenuation with less phase lag in the lower frequencies; this was demonstrated in Table 9.1.