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Filtered XLMS filter

The `dsp.FilteredXLMSFilter`

System
object™ computes output, error and coefficients using filtered-x least mean square FIR
adaptive filter.

To implement the adaptive FIR filter object:

Create the

`dsp.FilteredXLMSFilter`

object and set its properties.Call the object with arguments, as if it were a function.

To learn more about how System objects work, see What Are System Objects? (MATLAB).

`fxlms = dsp.FilteredXLMSFilter`

`fxlms = dsp.FilteredXLMSFilter(len)`

`fxlms = dsp.FilteredXLMSFilter(Name,Value)`

returns a
filtered-x least mean square FIR adaptive filter System
object, `fxlms`

= dsp.FilteredXLMSFilter`fxlms`

. This System
object is used to compute the filtered output and the filter error for a given
input and desired signal.

returns a `fxlms`

= dsp.FilteredXLMSFilter(`len`

)`FilteredXLMSFilter`

System
object, `fxlms`

, with the `Length`

property
set to `len`

.

returns a `fxlms`

= dsp.FilteredXLMSFilter(`Name,Value`

)`FilteredXLMSFilter`

System
object, `fxlms`

, with each specified property set to the
specified value. Enclose each property name in single quotes. Unspecified properties have
default values.

**For versions earlier than R2016b, use the step
function to run the System object algorithm. The arguments to
step are the object you created, followed by
the arguments shown in this section.**

**For example, y = step(obj,x) and y = obj(x) perform equivalent operations.**

`[y,err] = fxlms(x,d)`

`[`

filters the input `y`

,`err`

] = fxlms(`x`

,`d`

)`x`

, using `d`

as the desired
signal, and returns the filtered output `y`

and the filter error
`err`

. The System object estimates the filter weights needed to minimize the error
between the output signal and the desired signal. You can access these coefficients by
accessing the `Coefficients`

property of the object. This can be done
only after calling the object. For example, to access the optimized coefficients of the
`fxlms`

filter, call `fxlms.Coefficients`

after you
pass the input and desired signal to the object.

To use an object function, specify the
System
object as the first input argument. For
example, to release system resources of a System
object named `obj`

, use
this syntax:

release(obj)

[1] Kuo, S.M. and Morgan, D.R. *Active
Noise Control Systems: Algorithms and DSP Implementations*.
New York: John Wiley & Sons, 1996.

[2] Widrow, B. and Stearns, S.D. *Adaptive
Signal Processing*. Upper Saddle River, N.J: Prentice Hall,
1985.