DFD Windowed FIR Design VI

Digital Filter Design VIs and Functions

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Owning Palette: Advanced FIR Filter Design VIs

Installed With: Digital Filter Design Toolkit

Creates a finite impulse response (FIR) filter by using the window methods.

Example

Place on the block diagram

Find on the Functions palette

window specifies the time-domain window this VI uses.

0	None (default)
1	Hanning
2	Hamming
3	Blackman-Harris
4	Exact Blackman
5	Blackman
6	Flat Top
7	4 Term B-Harris
8	7 Term B-Harris
9	Low Sidelobe
30	Triangular

filter type specifies the type of filter that this VI creates.

0	Lowpass (default)
1	Highpass
2	Bandpass
3	Bandstop

order specifies the filter order. The value of order must be greater than zero. The default is 20. order +1 equals the number of coefficients or filter taps. Increasing the value can narrow the transition band.

high cutoff freq specifies the high cutoff frequency in hertz. The value must be greater than low cutoff freq. The default is 0.45. This VI uses this input only for bandpass and bandstop filter design. The cutoff frequency is the frequency with one-half magnitude response.

low cutoff freq specifies the low cutoff frequency in hertz. The default is 0.12. The cutoff frequency is the frequency with one-half magnitude response.

error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node.

	status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE.
	code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code.
	source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.

fs specifies the sampling frequency in hertz. The value must be greater than zero. The default is 1, which is the normalized sampling frequency.

filter out returns a new filter.

error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error.

	status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.
	code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code.
	source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

Example

Refer to the FIR Windowed Filter Design - DFD VI in the labview\examples\Digital Filter Design\AALXMPL directory for an example of using the DFD Windowed FIR Design VI.

Open example Browse related examples

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