Special FIR and IIR BI Notch Filters

Abstract

A methodology for designing FIR bi notch filters derived from second order prototype IIR notch filters is suggested. A special case when two notch frequencies ω 1 and ω 2 are such that [(cos ω 1 )(cos ω 2 ) = -1/2] has been discussed. The IIR bi notch filter design for this special case results reduction in the number of multipliers without affecting the response of the desired notch filter. For the referred condition, the required design weights of FIR bi notch filter reduce to almost half in number resulting in reduced computations.

Design and Analysis of IIR Notch Filter using LabVIEW

“…Therefore, the effective removal or reduction of noise in the field of signal processing is an active area of research. In order to keep tracking the frequencies changes in the input signal, the notch filters must be employed in the DSP system so as to update that system recursively [2] [3]. This notch filter is able to extract the desired sinusoid component of a given signal provided that the signal frequency remains constant.…”