R. Yang et al., DESIGN OF SHARP LINEAR-PHASE FIR BANDSTOP FILTERS USING THE FREQUENCY-RESPONSE-MASKING TECHNIQUE, Circuits, systems, and signal processing, 17(1), 1998, pp. 1-27
A novel computationally efficient realization of sharp linear-phase fi
nite impulse response (FIR) bandstop filters is proposed. The synthesi
s scheme for the bandstop filters is derived from variations of the fr
equency-response-masking technique. Five realization structures are pr
esented in this paper for the synthesis of five different classes of b
andstop filters. Approximate expressions for the optimal value of the
impulse response up-sampling ratio (M) and the corresponding number of
multipliers are derived.