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Member of the filter design class.

Syntax

[n, fb, ab, w] = firpmord(f, a, ripple)

[n, fb, ab, w] = firpmord(f, a, ripple, fs)

Description

Returns the order and normalized frequencies of the lowest order linear phase FIR filter with a given specification. The designed filter is an optimal equiripple filter that uses the Parks-McClellan algorithm.

Examples

Inputs

Name	Description
f	Specifies the cutoff frequencies of the filter. f is a vector of increasing positive numbers in the interval [0, fs/2].
a	Specifies the desired magnitudes at the f frequencies. a is a real vector.
ripple	Specifies the maximum deviation of ripples per band. ripple is a real vector.
fs	Specifies the sampling frequency. fs is a positive number. The default is 2.

Outputs

Name	Description
n	Returns the estimated filter order. n is a positive integer.
fb	Returns the normalized frequencies corresponding to f. fb is a real vector of increasing values in the interval [0, 1].
ab	Returns the magnitudes of the filter. ab is a real vector of the same size as fb.
w	Returns the weights of the filter. w is a vector of positive numbers of the same size as fb.

Examples

F = [100, 200];
A = [0, 1];
RIPPLE = [0.05, 0.02];
FS = 500;
[N, FB, AB, W] = firpmord(F, A, RIPPLE, FS)

Related Topics

fir1
fir2
firpm
remez
remezord