Recursive Filter

Recursive Filters are implemented as a cascade of a single pole Low-Pass Filter, a single pole High Pass Filter and a single pole notch filter. Zero-Phase is obtained using the forward-backward filtering technique: signals are filtered one time in the forward direction and another one after reversing the signal. The number of steps is two, which means that the signals are filtered twice through the aforementioned cascade.

"Recursive filters are an efficient way of achieving a long impulse response, without having to perform a long convolution. They execute very rapidly, but have less performance and flexibility than other digital filters. Recursive filters are also called Infinite Impulse Response (IIR) filters, since their impulse responses are composed of decaying exponentials. This distinguishes them from digital filters carried out by convolution, called Finite Impulse Response (FIR) filters."

From "The Scientist and Engineer's Guide to Digital Signal Processing", By Steven W. Smith, Ph.D.

Created with the Personal Edition of HelpNDoc: Easily create EBooks