gsignal (version 0.3-1)

pei_tseng_notch: Pei-Tseng notch filter

Description

Compute the transfer function coefficients of an IIR narrow-band notch filter.

Usage

pei_tseng_notch(w, bw)

Arguments

w

vector of critical frequencies of the filter. Must be between 0 and 1 where 1 is the Nyquist frequency.

bw

vector of bandwidths. Bw should be of the same length as w.

Value

List of class Arma with list elements:

b

moving average (MA) polynomial coefficients

a

autoregressive (AR) polynomial coefficients

Details

The filter construction is based on an all-pass which performs a reversal of phase at the filter frequencies. Thus, the mean of the phase-distorted and the original signal has the respective frequencies removed.

References

Pei, Soo-Chang, and Tseng, Chien-Cheng "IIR Multiple Notch Filter Design Based on Allpass Filter"; 1996 IEEE Tencon, doi: 10.1109/TENCON.1996.608814

See Also

Arma, filter

Examples

# NOT RUN {
## 50 Hz notch filter
fs <- 256
nyq <- fs / 2
notch <- pei_tseng_notch(50 / nyq, 2 / nyq)
freqz(notch, fs = fs)

# }