# fircls

Constrained-least-squares FIR multiband filter design

## Description

generates a length `b`

= fircls(`n`

,`f`

,`amp`

,`up`

,`lo`

)`n`

+ 1 linear phase FIR filter. The
frequency-magnitude characteristics of this filter match those given by vectors
`f`

and `amp`

. `up`

and
`lo`

are vectors with the same length as `amp`

. They
define the upper and lower bounds for the frequency response in each band.

## Examples

## Input Arguments

## Output Arguments

## Algorithms

The `fircls`

function uses an iterative least-squares algorithm to obtain
an equiripple response. The algorithm is a multiple exchange algorithm that uses Lagrange
multipliers and Kuhn-Tucker conditions on each iteration.

## References

[1] Selesnick, I. W., M. Lang, and C. S.
Burrus. “Constrained Least Square Design of FIR Filters without
Specified Transition Bands.” *Proceedings of the
1995 International Conference on Acoustics, Speech, and Signal Processing.* Vol.
2, 1995, pp. 1260–1263.

[2] Selesnick, I. W., M. Lang, and C. S. Burrus.
“Constrained Least Square Design of FIR Filters without Specified
Transition Bands.” *IEEE ^{®} Transactions on Signal
Processing*. Vol. 44, Number 8, 1996, pp. 1879–1892.

## Extended Capabilities

## Version History

**Introduced before R2006a**