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Polyphase FFT analysis filter bank

The `dsp.Channelizer`

System
object™ separates a broadband input signal into multiple narrow subbands using a fast
Fourier transform (FFT)-based analysis filter bank. The filter bank uses a prototype lowpass
filter and is implemented using a polyphase structure. You can specify the filter coefficients
directly or through design parameters.

To separate a broadband signal into multiple narrow subbands:

Create the dsp.Channelizer 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).

`channelizer = dsp.Channelizer`

`channelizer = dsp.Channelizer(M)`

`channelizer = dsp.Channelizer(Name,Value)`

creates a
polyphase FFT analysis filter bank System
object that separates a broadband input signal into multiple narrowband output
signals. This object implements the inverse operation of the
`channelizer`

= dsp.Channelizer`dsp.ChannelSynthesizer`

System
object.

creates an
`channelizer`

= dsp.Channelizer(M)*M*-band polyphase FFT analysis filter bank, with the NumFrequencyBands property set to *M*.

creates a polyphase FFT analysis filter bank with each specified property set to the
specified value. Enclose each property name in single quotes.`channelizer`

= dsp.Channelizer(`Name,Value`

)

`channOut = channelizer(input)`

separates the
broadband input signal into a number of narrow band signals contained in the columns of
the channelizer output. `channOut`

= channelizer(input)

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)

Specific to dsp.Channelizer

`coeffs` | Coefficients of prototype lowpass filter |

`tf` | Return transfer function of overall prototype lowpass filter |

`polyphase` | Return polyphase matrix |

`freqz` | Frequency response of filters in channelizer |

`fvtool` | Visualize the filters in the channelizer |

`bandedgeFrequencies` | Compute the bandedge frequencies |

`centerFrequencies` | Compute center frequencies |

`getFilters` | Return matrix of channelizer FIR filters |

Common to All System Objects

`step` | Run System object algorithm |

`clone` | Create duplicate System object |

`getNumInputs` | Number of inputs required to call the System object |

`getNumOutputs` | Number of outputs from calling the System object |

`isLocked` | Determine if System object is locked |

`release` | Release resources and allow changes to System object property values and input characteristics |

`reset` | Reset internal states of System object |

`dsp.ChannelSynthesizer`

|`dsp.DyadicAnalysisFilterBank`

|`dsp.FIRHalfbandDecimator`

|`dsp.FIRHalfbandInterpolator`

|`dsp.IIRHalfbandDecimator`

- Channel Synthesizer | Channelizer | Dyadic Analysis Filter Bank | Two-Channel Analysis Subband Filter

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