fvtool

(To be removed) Visualize frequency response of digital down converter or digital up converter filter cascade

Syntax

fvtool(Conv)

fvtool(Conv,Arithmetic=arithType)

Description

fvtool(Conv) plots the magnitude response of a digital down converter or digital up converter, Conv. By default, the object plots the cascade response up to the second CIC null frequency (or to the first when only one CIC null exists). To use this syntax, the object Conv must be locked.

fvtool(Conv,Arithmetic=arithType) specifies the arithmetic type of the filters inside the converter. Set the Arithmetic input to 'double', 'single', or 'fixed-point'. When the Conv object is in an unlocked state, you must specify the arithmetic type. When the Conv object is in a locked state, it ignores the arithmetic input argument.

For example, to plot the magnitude response of a digital down converter in an unlocked state, set the Arithmetic input.

dwnConv = dsp.DigitalDownConverter
fvtool(dwnConv,Arithmetic='fixed-point')

Examples

Magnitude Response of Digital Down Converter

Plot the magnitude response of the digital down converter using the fvtool function and the visualizeFilterStages function.

Create a dsp.DigitalDownConverter System object with the default settings.

dwnConv = dsp.DigitalDownConverter

Using the fvtool function, plot the magnitude response of the overall filter cascade. Set the arithmetic type to 'fixed-point'.

fvtool(dwnConv,'Arithmetic','fixed-point')

The visualizeFilterStages function in addition plots the magnitude response of the individual filters stages.

visualizeFilterStages(dwnConv,'Arithmetic','fixed-point')

Input Arguments

Conv — Digital down converter or digital up converter

dsp.DigitalDownConverter | dsp.DigitalUpConverter

Digital down converter or digital up converter, specified as a dsp.DigitalDownConverter or dsp.DigitalUpConverter System object™.

arithType — Arithmetic type

'double' (default) | 'single' | 'fixed-point'

When the Conv object is in an unlocked state, you must specify the arithmetic type. When the Conv object is in a locked state, it ignores the arithmetic input argument.

Version History

Introduced in R2012a

R2024b: fvtool will be removed

The fvtool function will be removed in a future release. Use the visualize function instead.

Update Code

This table shows how to update existing code to use the visualize function.

Discouraged Usage	Recommended Replacement
Create a dsp.DigitalDownConverter object with the default settings. dwnConv = dsp.DigitalDownConverter Plot the magnitude response of the overall filter cascade using fvtool. Set the arithmetic type to 'fixed-point'. fvtool(dwnConv,Arithmetic='fixed-point')	The visualize function plots the magnitude response of the overall filter cascade and the individual filter stages. visualize(dwnConv,Arithmetic='fixed-point')
Create a dsp.DigitalUpConverter object with the default settings. upConv = dsp.DigitalUpConverter Plot the magnitude response of the overall filter cascade using fvtool. Set the arithmetic type to 'fixed-point'. fvtool(upConv,Arithmetic='fixed-point')	The visualize function plots the magnitude response of the overall filter cascade and the individual filter stages. visualize(upConv,Arithmetic='fixed-point')