Design of Digital FIR Notch Filters from Second Order IIR Prototype

Abstract

A straightforward method has been suggested for the design of FIR notch filters starting from a second order IIR prototype. By appropriate choice of its length, the frequency response of the designed FIR filter can be made to match that of the IIR prototype very closely. Explicit mathematical formulas for computing the required weights have also been given.

Indexing terms:

• Notch filters
• FIR digital filters
• Signal processing