DESIGN OF PREDICTIVE IIR FILTERS VIA FEEDBACK EXTENSION OF FIR FORWARD PREDICTORS

Finite impulse response (FIR) predictors for polynomial signals and si nusoids are easy to design because of the available closed-form design formulae, On the other hand, those FIR predictors have two major draw backs: the passband gain peak is usually greater than +3 dB, and a lon g FIR structure is needed to attain high attenuation in the stopband, Both of these characteristics cause severe problems, particularly in c ontrol instrumentation when the predictor operates inside a closed con trol loop, In this paper, we present a novel feedback extension scheme for FIR forward predictors. This extension makes it possible to easil y design infinite impulse response (IIR) predictors with low passband ripple and high stopband attenuation, The new approach is illustrated with design examples.