Signal Processing Toolbox

Magnitude Specifications Region: Lowpass

IIR	FIR
Butterworth	Equiripple
Chebyshev Type I	Least-squares
Chebyshev Type II	Window
Elliptic	Constr. Least-Squares
Maximally flat	Complex Equirpple
	Maximally flat

IIR Butterworth

If Specify order is selected in the Filter Order region, the attenuation at the cutoff frequency is fixed at 3 dB (half the passband power).

If Minimum order is selected in the Filter Order region, select the units for magnitude response characteristics from the Units list:

• dB for magnitude response characteristics in decibels (default)
• Squared for squared magnitude response characteristics

Specify the magnitude response characteristics in the text boxes:

• Apass or Epass--passband ripple
• Astop or Estop--stopband attenuation

IIR Chebyshev Type I

If Specify order is selected in the Filter Order region, specify the passband ripple (Apass or Epass) in decibels.

If Minimum order is selected in the Filter Order region, select the units for magnitude response characteristics from the Units list:

• dB for magnitude response characteristics in decibels (default)
• Squared for squared magnitude response characteristics

Specify the following magnitude response characteristics in the text boxes:

• Apass or Epass--passband ripple
• Astop or Estop--stopband attenuation

IIR Chebyshev Type II

If Specify order is selected in the Filter Order region, specify the stopband attenuation (Astop or Estop) in decibels.

If Minimum order is selected in the Filter Order region, select the units for magnitude response characteristics from the Units list:

• dB for magnitude response characteristics in decibels (default)
• Squared for squared magnitude response characteristics

Specify the following magnitude response characteristics in the text boxes:

• Apass or Epass--passband ripple
• Astop or Estop--stopband attenuation

IIR Elliptic

Select the units for magnitude response characteristics from the Units list:

• dB for magnitude response characteristics in decibels (default)
• Squared for squared magnitude response characteristics

Specify the magnitude response characteristics (in dB) in the text boxes:

• Apass or Epass--passband ripple
• Astop or Estop--stopband attenuation

IIR Maximally Flat

The magnitude at cutoff frequencies is fixed at half the passband gain (-3dB).

FIR Equiripple

If Specify order is selected in the Filter Order region, specify the following relative weights in the text boxes:

• Wpass--weight in the passband
• Wstop--weight in the stopband

If Minimum order is selected in the Filter Order region, select the units for magnitude response characteristics from the Units list:

• dB for magnitude response characteristics in decibels (default)
• Linear for linearly scaled magnitude response characteristics

Specify the following magnitude response characteristics in the text boxes:

• Apass or Dpass--passband ripple
• Astop or Dstop--stopband attenuation

FIR Least-Squares

Specify the magnitude weights, as linear multipliers, in the text boxes:

• Wpass--weight in the passband
• Wstop--weight in the stopband

FIR Window

If Specify order is selected in the Filter Order region, the attenuation at the cutoff frequency is fixed at 6 dB (half the passband gain).

For the Kaiser window option, if Minimum order is selected in the Filter Order region, select the units for magnitude response characteristics from the Units list:

• dB for magnitude response characteristics in decibels (default)
• Linear for linearly scaled magnitude response characteristics

Specify the following magnitude response characteristics in the text boxes:

• Apass or Dpass--passband ripple
• Astop or Dstop--stopband attenuation

FIR Constr. Least-Squares

Specify the magnitude response characteristics in the text boxes:

• Dpass--Upper and Lower bounds of the passband.
• Dstop--Upper and Lower bounds of the stopband

FIR Complex Equiripple

Specify the following relative weights in the text boxes:

• Wstop1 and Wstop2--weights in the stopbands
• Wpass--weight in the passband

FIR Maximally Flat

The magnitude at cutoff frequencies is fixed at half the passband gain (-3dB).

Magnitude Specifications Region

Magnitude Specifications Region: Raised Cosine

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