How to test digital filters?

1. How do I know if my digital filter is stable?
2. How do digital filters work?
3. What are the two types of digital filters?
4. How do you find the order of digital filters?

How do I know if my digital filter is stable?

A digital filter is stable if and only if all the poles of the irreducible filter transfer function lie inside the unit circle in the z plane. Any pole outside the unit circle introduces an exponentially increasing component in the filter's impulse response, thus causing the filter to be unstable.

How do digital filters work?

Filters function by blocking (suppressing) given frequency components in a signal and passing the original signal minus these suppressed components to the output. In contrast to analog filters, digital filters work by performing mathematical operation on the signal.

What are the two types of digital filters?

There are two fundamental types of digital filters: finite impulse response (FIR) and infinite impulse response (IIR).

How do you find the order of digital filters?

The order of a digital filter is the number of previous inputs (stored in the processor's memory) used to calculate the current output. Thus: 1. Examples (1) and (2) above are zero-order filters, as the current output yn depends only on the current input xn and not on any previous inputs.