Output length of an IIR Filter

In general, the output sequence of an IIR filter has an infinite length, even for a finite length input sequence.

1. What is the output of FIR filter?
2. What is length of FIR filter?
3. How do you find the length of an impulse response?
4. Why IIR filter is infinite?

What is the output of FIR filter?

In other words if you put an “impulse” into a FIR filter which consists of a “1” sample followed by a large number of “0” samples, the output of the filter will be simply the set of coefficients, as the 1 valued sample moves past each coefficient in turn to form the output.

What is length of FIR filter?

Filtering the upsampled sequence by an FIR lowpass filter designed with the filter length N = 159 and a cutoff frequency of 1250 Hz at the sampling rate of 3 × 8000 = 24,000 Hz.

How do you find the length of an impulse response?

@AnurananDas: The impulse response h[n] is given by the polynomial coefficients: H(z)=∑N−1n=0h[n]z−n, and the length N of the impulse response equals the number of coefficients, i.e., one plus the order of the polynomial.

Why IIR filter is infinite?

Infinite impulse response (IIR) filters are based on analog filters, where the frequency response is defined by both poles and zeros. Finite impulse response filters, in contrast, only have zeros. The presence of poles in the IIR filter causes the impulse response to be infinitely long.