Nonrecursive filter

A non-recursive filter only uses input values like x[n − i], unlike recursive filter where it uses previous output values like y[n-i]. Non-recursive digital filters are often known as Finite Impulse Response (FIR) Filters as a non-recursive digital filter has a finite number of coefficients in the impulse response h[n].

Non-recursive Filter Example: y[n] = 0.5x[n − 1] + 0.5x[n].

Recursive Filter Example: y[n] = 0.5y[n − 1] + 0.5x[n].