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Direct form FIR fullband differentiator filter

`dsp.Differentiator`

applies a fullband differentiator
filter on the input signal to differentiate all its frequency components.
This object uses an FIR equiripple filter design to design the differentiator
filter. The ideal frequency response of the differentiator is $$D(\omega )=j\omega $$ for $$-\pi \le \omega \le \pi $$. You can design
the filter with minimum order with a specified order. This object
supports fixed-point operations.

To filter each channel of your input:

Define and set up your differentiator. See Construction.

Call

`step`

to filter each channel of the input signal according to the properties of`dsp.Differentiator`

. The input signal can be a real-valued or complex-valued column vector or matrix. If the input signal is a matrix, each column of the matrix is treated as an independent channel. The number of rows in the input signal denotes the channel length. The data type of the input can be double, single, or fixed-point data type. The number of channels cannot change between calls to the`step`

method. The data type characteristics (double, single, or fixed-point) and the real-complex characteristics (real or complex valued) must be the same for the input data and output data.

Starting in R2016b, instead of using the `step`

method
to perform the operation defined by the System
object™, you can
call the object with arguments, as if it were a function. For example, ```
y
= step(obj,x)
```

and `y = obj(x)`

perform
equivalent operations.

`DF = dsp.Differentiator`

returns a differentiator, `DF`

,
with the default settings. Calling `step`

with the
default property settings filters the input data with a minimum-order
filter that has a passband ripple of 0.1 dB.

sets
each property Name to the specified Value. Unspecified properties
have default values.`DF`

= dsp.Differentiator(`Name,Value`

)

getFilter | Get underlying FIR filter |

reset | Reset internal states of differentiator |

step | Differentiate input signal with respect to time |

For additional methods, see Analysis Methods for Filter System Objects.

For a complete list of analysis methods supported for the `dsp.Differentiator`

object,
enter `dsp.Differentiator.helpFilterAnalysis`

at
the MATLAB^{®} command prompt.

Common to All System Objects | |
---|---|

`clone` | Create System object with same property values |

`getNumInputs` | Expected number of inputs to a System object |

`getNumOutputs` | Expected number of outputs of a System object |

`isLocked` | Check locked states of a System object (logical) |

`release` | Allow System object property value changes |

[1] Orfanidis, Sophocles J.* Introduction to Signal
Processing*. Upper Saddle River, NJ: Prentice-Hall, 1996.

Differentiator Filter | `dsp.BiquadFilter`

| `dsp.FIRFilter`

| `dsp.HighpassFilter`

| `dsp.VariableBandwidthFIRFilter`

| `dsp.VariableBandwidthIIRFilter`

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