Biosignal Filtering VI

Owning Palette: Biosignal Preprocessing VIs

Requires: Biomedical Toolkit

Filters biosignals with classical filters, such as lowpass, highpass, bandpass, bandstop filters, as well as notch filter and comb filter.

You must manually select the polymorphic instance to use.

Examples

Biosignal Filtering (Waveform Classical Filter)

	filter type specifies the classical filter to apply to the input biosignal. 0 Lowpass (default) 1 Highpass 2 Bandpass 3 Bandstop
	initialize? specifies whether to initialize the internal state of the VI. This VI performs calculations that are dependent on all previous data since the VI last ran or since you set initialize? to TRUE. When initialize? is TRUE, this VI restarts the calculation dependency. The default is FALSE.
	biosignal in specifies the biosignal to filter.
	freq specs specifies the frequency specifications for the classical filter. fpass 1 specifies the first passband edge frequency, in hertz. The default is 0.2. fpass 2 specifies the second passband edge frequency, in hertz. This VI ignores fpass 2 for lowpass and highpass filters. The default is 0. fstop 1 specifies the first stopband edge frequency, in hertz. The default is 0.3. fstop 2 specifies the second stopband edge frequency, in hertz. This VI ignores fstop 2 for lowpass and highpass filters. The default is 0.
	ripple specs specifies the ripple specifications for the classical filter. passband specifies the ripple level in the passband. The default is 0.1. stopband specifies the ripple level in the stopband. The default is 60. dB on? specifies whether this VI applies a decibel scale or a linear scale to the ripple levels. The default is TRUE, which means to apply a decibel scale to the ripple levels.
	error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
	design method specifies the method that this VI uses to design the filter. 0 Butterworth 1 Chebyshev 2 Inverse Chebyshev 3 Elliptic (default) 4 Kaiser Window 5 Dolph-Chebyshev Window 6 Equi-Ripple FIR
	biosignal out returns the filtered biosignal.
	filter out returns the filter that this VI applies to the input biosignal.
	error out contains error information. This output provides standard error out functionality.

Biosignal Filtering (Array Classical Filter)

	filter type specifies the classical filter to apply to the input biosignal. 0 Lowpass (default) 1 Highpass 2 Bandpass 3 Bandstop
	initialize? specifies whether to initialize the internal state of the VI. This VI performs calculations that are dependent on all previous data since the VI last ran or since you set initialize? to TRUE. When initialize? is TRUE, this VI restarts the calculation dependency. The default is FALSE.
	biosignal in specifies the biosignal to process.
	freq specs specifies the frequency specifications for the classical filter. fpass 1 specifies the first passband edge frequency, in hertz. The default is 0.2. fpass 2 specifies the second passband edge frequency, in hertz. This VI ignores fpass 2 for lowpass and highpass filters. The default is 0. fstop 1 specifies the first stopband edge frequency, in hertz. The default is 0.3. fstop 2 specifies the second stopband edge frequency, in hertz. This VI ignores fstop 2 for lowpass and highpass filters. The default is 0.
	ripple specs specifies the ripple specifications for the classical filter. passband specifies the ripple level in the passband. The default is 0.1. stopband specifies the ripple level in the stopband. The default is 60. dB on? specifies whether this VI applies a decibel scale or a linear scale to the ripple levels. The default is TRUE, which means to apply a decibel scale to the ripple levels.
	error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
	sampling rate specifies the sampling frequency of the input biosignal, in hertz. sampling rate must be greater than 0. The default is 1, which is the normalized sampling frequency.
	design method specifies the method that this VI uses to design the filter. 0 Butterworth 1 Chebyshev 2 Inverse Chebyshev 3 Elliptic (default) 4 Kaiser Window 5 Dolph-Chebyshev Window 6 Equi-Ripple FIR
	biosignal out returns the filtered biosignal.
	filter out returns the filter that this VI applies to the input biosignal.
	error out contains error information. This output provides standard error out functionality.

Biosignal Filtering (Waveform Notch or Comb)

	filter type specifies the type of the filter to apply to the input biosignal. 0 Notch (default)—Specifies to apply notch filters to the input biosignal. 1 Comb—Specifies to apply comb filters to the input biosignal.
	initialize? specifies whether to initialize the internal state of the VI. This VI performs calculations that are dependent on all previous data since the VI last ran or since you set initialize? to TRUE. When initialize? is TRUE, this VI restarts the calculation dependency. The default is FALSE.
	biosignal in specifies the biosignal to filter.
	f0 specifies the center frequency of the first non-zero notch or peak, in hertz. The default is 0.10.
	Df specifies the full bandwidth at the level of –Ab, in hertz. The default is 0.02.
	error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
	Ab specifies the attenuation, in decibels, that corresponds to the bandwidth. The default is 3.0103, which corresponds to 3 dB bandwidth, the commonly used bandwidth of a filter.
	biosignal out returns the filtered biosignal.
	filter out returns the filter that this VI applies to the input biosignal.
	error out contains error information. This output provides standard error out functionality.

Biosignal Filtering (Array Notch or Comb)

	filter type specifies the type of the filter to apply to the input biosignal. 0 Notch (default)—Specifies to apply notch filters to the input biosignal. 1 Comb—Specifies to apply comb filters to the input biosignal.
	initialize? specifies whether to initialize the internal state of the VI. This VI performs calculations that are dependent on all previous data since the VI last ran or since you set initialize? to TRUE. When initialize? is TRUE, this VI restarts the calculation dependency. The default is FALSE.
	biosignal in specifies the biosignal to process.
	f0 specifies the center frequency of the first non-zero notch or peak, in hertz. The default is 0.10.
	Df specifies the full bandwidth at the level of –Ab, in hertz. The default is 0.02.
	error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
	sampling rate specifies the sampling frequency of the input biosignal, in hertz. sampling rate must be greater than 0. The default is 1, which is the normalized sampling frequency.
	Ab specifies the attenuation, in decibels, that corresponds to the bandwidth. The default is 3.0103, which corresponds to 3 dB bandwidth, the commonly used bandwidth of a filter.
	biosignal out returns the filtered biosignal.
	filter out returns the filter that this VI applies to the input biosignal.
	error out contains error information. This output provides standard error out functionality.

Examples

Refer to the following VIs for examples of using the Biosignal Filtering VI:

• Biosignal Preprocessing Comparison VI: labview\examples\Biomedical\Biosignal
• Biosignal Logger VI: labview\examples\Biomedical\Biosignal