DFD Raised Cosine Design VI

Digital Filter Design VIs and Functions

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Owning Palette: Multirate Filter Design VIs

Installed With: Digital Filter Design Toolkit

Creates a raised cosine or a root-raised cosine finite impulse response (FIR) filter.

You can use the filter as a single-rate filter, an interpolation filter, or a decimation filter.

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

factor specifies the sampling frequency conversion factor of the multirate filter. The default is 4. The passband of the filter depends on factor by Nyquist sampling theorem.

order specifies the filter order. The value must be an even integer that is greater than zero. The default is 10. If order is an odd number, this VI returns an error. Increasing the value of order can increase the stopband attenuation.

roll off determines the relative transition bandwidth, which equals (transition band)/(2*passband + transition band). The default is 0.2. roll off must be in the range of [0,1]. If the value of factor is fixed, a smaller roll off value results in a narrower transition bandwidth.

type specifies the type of filter that this VI creates.

0	Raised Cosine (default)
1	Root Raised Cosine

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.

filtering mode specifies the processing mode of the filter that this VI creates.

0	No Rate Change—Does not change the sampling frequency of a signal.
1	Interpolation—Increases the sampling frequency of a signal to a higher sampling frequency that differs from the original frequency by an integer value. Interpolation also is known as up-sampling.
2	Decimation (default)—Reduces the sampling frequency of a signal to a lower sampling frequency that differs from the original frequency by an integer value. Decimation also is known as down-sampling.

multirate filter out returns a new multirate filter.

order out returns the actual order of the 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 Raised Cosine Filter VI in the labview\examples\Digital Filter Design\Floating-Point Filters\Multirate directory for an example of using the DFD Raised Cosine Design VI.

Open example Browse related examples

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