Nonrecursive filter


In mathematics, a nonrecursive filter only uses input values like x, unlike recursive filter where it uses previous output values like y.
In signal processing, non-recursive digital filters are often known as Finite Impulse Response filters, as a non-recursive digital filter has a finite number of coefficients in the impulse response h.
Examples:
  • Non-recursive filter: y = 0.5x + 0.5x
  • Recursive filter: y = 0.5y + 0.5x
An important property of non-recursive filters is, that they will always be stable. This is not always the case for recursive filters.