Company Events Academic Community Support Solutions Products & Services Contact NI MyNI

fir_win (MathScript RT Module Function)

LabVIEW 2012 MathScript RT Module Help

Edition Date: June 2012

Part Number: 373123C-01

»View Product Info
Download Help (Windows Only)

Owning Class: filter design

Requires: MathScript RT Module

Syntax

b = fir_win(n, w)

b = fir_win(n, w, option)

b = fir_win(n, w, window)

b = fir_win(n, w, s)

b = fir_win(n, w, option, window)

b = fir_win(n, w, option, s)

b = fir_win(n, w, option, window, s)

Legacy Name: fir1

Description

Uses the window design method to design a linear phase FIR filter. This function windows the impulse response with a Hamming window by default.

Examples

Inputs

Name Description
n Specifies the filter order. n is a nonnegative integer. n must be even for filters with a non-zero gain at the Nyquist frequency. If n does not meet this condition, LabVIEW increases n by 1.
w Specifies the cutoff frequencies of the filter. w is real scalar or ascending vector with elements between 0 and 1. 1 represents the Nyquist frequency. fir_win generally designs a multiband FIR filter with bands 0<w<w1w1<w<w2wn<w<1.
option Specifies the type of filter to design. option is a string that accepts the following values.

'low' (default) Designs a lowpass filter.
'high' Designs a highpass filter.
'bandpass' Designs a bandpass filter.
'stop' Designs a stopband filter.
'DC-0' Designs a multiband filter whose first band is a stopband.
'DC-1' Designs a multiband filter whose first band is a passband.
window Specifies the window coefficients. The length of window must equal n + 1. If n is even and the filter has a non-zero gain at the Nyquist frequency, the length of window must equal n + 2.
s Specifies whether the magnitude of the designed filter is normalized. s is a string that accepts the following values.

'scale' (default) Directs LabVIEW to scale the filter coefficients.
'noscale' Directs LabVIEW not to scale the filter coefficients.

Outputs

Name Description
b Returns the filter coefficients of order n. b is a real vector.

Details

The following table lists the support characteristics of this function.

Supported in the LabVIEW Run-Time Engine Yes
Supported on RT targets Yes
Suitable for bounded execution times on RT Not characterized

Examples

N = 5;
W = 0.2;
B = fir_win(N, W, 'low', win_hann2(6))

Related Topics

filter
fir_fs
fir_gauss
fir_lsq
win_hamming


 

Your Feedback! poor Poor  |  Excellent excellent   Yes No
 Document Quality? 
 Answered Your Question? 
Add Comments 1 2 3 4 5 submit