Version:

Last Modified: March 15, 2017

Designs an elliptic (Cauer) filter. If you specify w, this function generates a lowpass filter of order n. If you specify w1 and w2, this function generates a bandpass filter of order 2n. [z, p, k] and [as, bs, cs, ds] generate the zero-pole-gain representation and the state-space representation, respectively, of the filter.

[b, a] = iir_elliptic(n, dbp, dbs, w)

[b, a] = iir_elliptic(n, dbp, dbs, w, 's')

[b, a] = iir_elliptic(n, dbp, dbs, [w1,w2])

[b, a] = iir_elliptic(n, dbp, dbs, [w1,w2], 's')

[b, a] = iir_elliptic(n, dbp, dbs, w, option)

[b, a] = iir_elliptic(n, dbp, dbs, w, option, 's')

[b, a] = iir_elliptic(n, dbp, dbs, [w1,w2], 'stop')

[b, a] = iir_elliptic(n, dbp, dbs, [w1,w2], 'stop', 's')

[z, p, k] = iir_elliptic(n, dbp, dbs, w)

[z, p, k] = iir_elliptic(n, dbp, dbs, w, 's')

[z, p, k] = iir_elliptic(n, dbp, dbs, [w1,w2])

[z, p, k] = iir_elliptic(n, dbp, dbs, [w1,w2], 's')

[z, p, k] = iir_elliptic(n, dbp, dbs, w, option)

[z, p, k] = iir_elliptic(n, dbp, dbs, w, option, 's')

[z, p, k] = iir_elliptic(n, dbp, dbs, [w1,w2], 'stop')

[z, p, k] = iir_elliptic(n, dbp, dbs, [w1,w2], 'stop', 's')

[as, bs, cs, ds] = iir_elliptic(n, dbp, dbs, w)

[as, bs, cs, ds] = iir_elliptic(n, dbp, dbs, w, 's')

[as, bs, cs, ds] = iir_elliptic(n, dbp, dbs, [w1,w2])

[as, bs, cs, ds] = iir_elliptic(n, dbp, dbs, [w1,w2], 's')

[as, bs, cs, ds] = iir_elliptic(n, dbp, dbs, w, option)

[as, bs, cs, ds] = iir_elliptic(n, dbp, dbs, w, option, 's')

[as, bs, cs, ds] = iir_elliptic(n, dbp, dbs, [w1,w2], 'stop')

[as, bs, cs, ds] = iir_elliptic(n, dbp, dbs, [w1,w2], 'stop', 's')Legacy name: ellip

Filter order. n is a positive integer.

Ripple in the passband. dbp is a decibel value that must be greater than zero.

Minimum stopband attenuation. dbs is a decibel value that must be a real scalar.

Cutoff frequency of the filter. w is a real number between 0 and 1. 1 represents the Nyquist frequency. If you specify 's', w can be any positive number.

Low and high cutoff frequency as matrix. w1 must fall in the range [0, 1]. If you specify 's', w1 can be any positive number. w2 must fall in the range [0, 1] and must be greater than w1. If you specify 's', w2 can be any positive number.

Type of filter to design. option is a string that accepts the following values:

Name | Description |
---|---|

'low' | Designs a lowpass filter. |

'high' | Designs a highpass filter. |

**Default: ** 'low'

Directs MathScript to design a stopband filter. If you do not specify 'stop' and you specify w1 and w2, MathScript designs a bandpass filter.

Directs MathScript to design an analog elliptic (Cauer) filter.

Numerator of the filter under design. b is the forward filter coefficient of order n. b is a real vector.

Denominator of the filter under design. a is the backward filter coefficient of order n. a is a real vector.

Zeros of the filter. z is a vector.

Poles of the filter. p is a vector.

Gain of the filter. k is a real number.

A coefficients of the filter. as is a matrix.

B coefficients of the filter. bs is a matrix.

C coefficients of the filter. cs is a matrix.

D coefficients of the filter. ds is a matrix.

N = 5; DBP = 0.5; DBS = 20; W = 0.4; [B, A] = iir_elliptic(N, DBP, DBS, W)

**Where This Node Can Run: **

Desktop OS: Windows

FPGA: This product does not support FPGA devices