Digital systems
FIR

Filters with finite response. Not containing feedback and this is nonrecursive (convolution) filters. Transfer of causal (only positive values n) filtering by:

(067)

and differential equation is:

(068)

FIR filter are always stable.

Mostly used structure is transversal filter. It’s delaying line with switches to multipliers. Filter computing weighted moving average from + 1 last value. Coeficients are values from impulse response – bn h(n).

Fig. 8.1: Scheme for transversal FIR filter

Filter delaying signal for (069)beats and stabilize after + 1 beats.